Journal of Sustainable Agriculture and the Environment (JSAE)

Factors Influencing Farmers’ Participation in Sweet Potato Farming Practices in Owerri North Local Government Area, Imo State, Nigeria

C. U. Nwaobiala — 2022-11-06

The study analyzed farmers’ participation in sweet potato farming practices in Imo State, Nigeria. Multi-stage random sampling technique was used to select sixty (80) farmers. Data were collected through a structured questionnaire and analyzed with descriptive statistics and inferential statistics (probit and multiple regression analyses). Result showed half (50.0%) of the farmers were males and females respectively, with mean ages of 45.5 years, 56.7% were married, mean farm size of 0.5 hectares and intercropped cassava/maize/sweet potato (63.3%). The result indicates that farmers’ sourced information on sweet potato farming practices from personal observations (90.0%), fellow farmers (86.7%) and television programmes (78.67%), while 63.3% intercropped sweet potato vines with cassava and maize. The farmers had favourable perception =2.9) and had high participation =2.3) in sweet potato cultivar characteristics. Probit regression result showed that coefficient for tuber yield, vine yield, early maturity, disease and pest tolerant and good culinary test influenced farmers’ participation of sweet potato farming practices. Multiple regression result showed that coefficients of gender, age, marital status, occupation and farm size influenced farmers’ participation of sweet potato production activities in the study area. Breeding of early maturing, high yielding and disease resistant varieties by researchers and access to land for sweet potato farming activities were advocated.

Optimization of mixed spices from scent leaf, curry and African Black Pepper

Kuyik Solomon Abasiekong — 2022-11-06

D-optimal mixture design and the numerical optimization technique were used to optimize mixed spices produced from three leafy vegetables Scent leaf (Ocimum grastissimum), Curry (Murray koemigii) and African black pepper (Piper guineense), as the factors. The spices were blended according to the mixture design combinations generated based on the three factors and modelled with three sensory attributes (flavour, appearance and general acceptability) as the responses. Results indicated that 80:10:10 (scent leaf:curry:African black pepper leaves) mixed spice which was outstanding in sensory evaluation with scores of 8 (flavor), 7 (appearance) and 8 (general acceptability), was selected as the optimized product. Further evaluation of the optimized product showed a mineral profile of 1.462 (zinc), 0.326 (copper), 489.476 (calcium), 6.418 (magnesium), and 6.169 mg/100g (iron). Phytochemical profile showed the presence of phenol (0.15), tannin (0.72), phytase (0.56), flavonoid (0.73), sterol (0.14), alkaloid (0.95), oxalate (0.53) and saponin (0.94 mg/100g). Meanwhile the heavy metal screening showed that lead and cadmium were not detected. These results show that local spices, besides possessing excellent nutraceutical properties, can be processed into highly acceptable novel flavor enhancing products.

Comparison of Different Methods for the Assessment of Soil Organic Carbon in Northern Guinea Savanna Zone of Nigeria

A A. Mustapha — 2022-11-07

In Nigeria, Walkley-Black is the most widely used method for soil organic carbon determination. The organic carbon content of the Northern Guinea Savanna soil is low and incomplete oxidation of carbon occurs in the method of determination (Walkley-Black). Three different methods; Tube digestion, Loss on ignition and Potassium permanganate were evaluated and the results obtained compared with Walkley-Black. Soil were sampled from the Northern Guinea Savanna of Nigeria and amount of carbon evaluated using the aforementioned methods. Percentage of carbon recovered ranged from 50.637 to 132.059 and correction factor (CF) varied from 0.757 to 1.975. The result showed low correlation among the used methods.The highest and lowest coefficient of determination (R²) was found in Tube digestion (0.113) and loss on ignition methods (0.014) respectively. The results of the recovery percentages indicates that the loss on ignition and tube digestion were almost similar with the results obtained using the Walkey-Black and as such may be used as an alternative to Walkley-Black method in soil testing laboratories for soils of the Northern Guinea Savanna of Nigeria.

Utilisation of Information and Communication Technologies for Entrepreneurial Skills Development among Students of Selected Agricultural Institutions in Ibadan Oyo State, Nigeria

A. S. Adeoye — 2022-11-07

The challenges of unemployment as a result of limited white-collar jobs prompted the investigation into the study of utilisation of ICTs for entrepreneurial skills development to help train and expose students to opportunities after graduation from school. Hence, the study investigated the utilisation of Information and Communication Technologies for entrepreneurial skills development among students of selected agricultural institutions in Ibadan, Oyo state. The parameters examined were: availability of ICTs, the extent of ICTs utilization, and constraints experienced by respondents in utilizing ICTs in the study area. A well-structured questionnaire was used for collection of data through a purposive and random sampling procedure to select a sample of 105 students for the study. The data collected were analyzed with descriptive statistics such as frequencies and percentages; and inferential statistics like Pearson product moment correlation, PPMC to draw inferences between variables of the hypotheses. The result showed that majority of the respondents (77.2%) ascertained that personal computers were available in their institutions whereas 72.6% of the respondents possessed mobile phones as ICTs devices in the study area. Furthermore, the findings revealed low extent of ICTs utilization among the students in the study area. The findings also revealed that there were major constraints hampering ICTs utilization in the study area. There was no significant relationship between availability of ICT devices and utilization of the ICTs for entrepreneurial skills development (r= 0.117, p= 0.245), whereas there was significant relationship between the constraints experienced by the respondents and utilization of ICTs for entrepreneurial skills development (r= 0.060, p= 0.026). The study however concluded that generally the utilization of ICTs for entrepreneurial skills development among the respondents was at a low level due to low extent of ICTs use and some constraining factors among the students in the study area. Therefore, the study recommends that awareness creation should be carried out to educate and elicit students’ interest on the importance and use of ICTs among students of these institutions, and these institutions should integrate ICTs to strengthen their curriculum for entrepreneurial studies in the study area.

A translog stochastic frontier analyses of technical, economic and allocative efficiencies in yam production in Ebonyi State, Nigeria

D. O. Ohajianya — 2022-11-07

This study estimated technical, economic, allocative efficiencies and determinants of allocative efficiency of yam farmers in Ebonyi State, Nigeria using translog stochastic frontier production function. Data were collected with structured questionnaire from 160 proportionately and randomly selected yam farmers. Data were analyzed using descriptive statistics such as mean, standard deviation, frequency distribution and percentages, as well as econometric tool of translog stochastic frontier production function. Results show that the mean age, level of education, farm size farming experience, extension contact, household size and anuual farm income were 48.2 years, 9.3 years, 1.02 hectares, 18.7 years, 0.53 visit, 8 persons and N431603 respectively. The mean technical, economic and allocative efficiencies were 72.12%, 67.55%, and 86.31% respectively. Yam farmers are allocative inefficient in resource utilization. The sources of allocative inefficiency were age, level of education, farming experience, farm size, marital status, extension contact, credit access, household size, and off-farm employment. Yam farmers should endeavor to properly allocate resource inputs to achieve improvement in allocative efficiency.

Economic Analysis of Cassava (Manihot esculenta Crantz) Production in Akinyele Local Government Area of Oyo State, Nigeria

K. A. Jatto — 2022-11-07

The study examined the economic analysis of Cassava production in Akinyele Local Government Area of Oyo State. Multistage random sampling technique was used to select a sample size of 180 respondents for the study. Data collected were analyzed with descriptive statistics such as frequency, percentages, and chats while inferential statistics used were budgetary techniques and regression analysis. The results showed that majority of the respondents (83.9%) were males, 75.6% of the farmers were married and 83.3% of the respondents were having family size of 4-9. Majority of the respondents (88.3%) had formal education, 80.5% of the respondents had farming experience of more than16 years. Costs and returns for cassava production were analyzed with budgetary techniques and the result revealed that for a hectare of cassava there was gross margin of ₦72,318.75 Kobo and the net profit of ₦64,575.00Kobo with a cost benefit ratio of ₦1.85Kobo implying that for every ₦1.00 invested in cassava production, there was corresponding profit of 85Kobo. Nevertheless, the result further showed there was no efficient allocation of variable inputs (resource) due to negative coefficients of these explanatory variables but there was significant relationship to the net profit of the cassava farmers in the study area. Therefore, there is need for cassava farmers to improve on their resource allocation to make their production robust and to boost their productivity. The study further recommended that the cassava farmers should be trained on latest innovative practices in cassava production and proper advisory services must be given to them by the subject matter specialists on resource allocation for optimal profitability in their production in Akinyele Local Government Area of Oyo State, Nigeria.

Environmental Risks Management Practices among Rice Farmers in Rice Producing Areas of Imo State, Nigeria

T. A. Amusa — 2022-11-07

The study estimated environmental risks management practices among rice farmers in rice producing areas of Imo State, Nigeria. Multistage, purposive and random sampling techniques were used to sample 120 rice farmers across four LGAs of Imo State. Using well structured close-ended questionnaire, data were collected from 120 rice farmers. Out of the 120 questionnaires administered, 133 were properly responded to and considered suitable for analysis. Data were analysed using frequency, percentage, means and Ordinary Least Square (OLS) multiple regression analysis. The results show that pests and diseases outbreak, occasional flooding, destruction by birds, soil fertility depletion and injury during field operation are some of environmental risks facing the rice farmers. Some environmental risk management measures practiced by rice farmers include: wearing of boots in rice farms, construction of Birds scaring objects and planting of pest and disease resistant variety of rice. The result of the Ordinary Least Squares regression analysis shows that the semi-log functional form had the best fit with R² value of 0.9438, F-value of 158.38 and Prob>F value of 0.0000. Out of the 11 explanatory variables specified in the model, eight variables which include: education, gender, household size, cooperative, access to credit, extension contact, farm size and income statistically and significantly influenced rice farmers’ practices of environmental risk measures at 1% and 5% level of significance. Based on the findings, the study recommended proactive government’s intervention policies and programmes to rice farming in order to cushion the effects of environmental risks facing rice farmers among others.

Analysis of Cassava Farmers’ Response to Climate Change Adaptation: Implication for Sustainable Food Production in Nigeria

C. A. Kalu — 2022-11-07

The study examined how smallholder cassava farmers responded to changes in climate by identifying adaptation strategies adopted by the farmers and its determinants. In addition, the study analyzed the trend of production, productivity, and hectarage of cassava in Nigeria from 1980-2017. Multinomial logit model and exponential trend equation were employed to analyze the obtained data. The cassava farmers studied adopted use of irrigation (10%), livestock ownership 53.24%), mixed cropping (79.86%) and use of improved crop variety (92.81%) as major adaptation methods. The adaptive approaches used by cassava farmers were determined by farming experience, level of education and ownership of transport. The empirical trend analysis revealed that the coefficients of cassava output and hectarage were - 45.15 and -43.42 respectively and statistically significant at 1% implying a decrease in cassava output and hectarage within the period under study. It was further revealed that the marginal effects for the level of education and ownership of a means of transport were 0.11 and – 0.12 respectively. The implication of this result is that one unit increase in level of education and ownership of means of transport of a cassava farmer is associated with 11% more likely and 12% less likely that the farmer will adopt livestock ownership as adaptation strategy over the use of new crop variety. Therefore, from the established result, it was suggested that educational campaign on climate adaptation strategies should be embarked on so as to hearten the consciousness of cassava farmers on adaption strategies to climate change. More so improved cassava varieties are required for sustainable cassava production and food security in Nigeria.

Growth and Yield Performance of Bambara nuts (Vigna subterranean (L). Verdc) as Influenced by Cropping System and Plant Spacing in Yola, Nigeria

I. Audu — 2022-11-07

The experiment was conducted to evaluate the growth and yield performance of Bambara nuts (Vigna subterramean (L) Verdc) under a cropping system (bambara nuts/maize intercrop) and different plant spacing. The experiment was conducted during the 2017 and 2018 cropping seasons at the Teaching and Research Farm of the Department of Crop Production and Horticulture, Modibbo Adama University of Technology Yola, Nigeria. The field experiments were factorial design laid out in a split plot design. The treatments consisted of three (3) plant spacings of 20, 25 and 30 cm which were assigned to main plot treatment while maize variety samaz 17 and bambara nut were assigned to the sub- plots treatment was replicated three (3) times. Performance parameters measured included establishment count expressed in percentage, plant height, harvest index, days to 50% flowering, shelling percentage, weight of dry pod, weight of seed and total yields. Results showed that plant spacing and maize-bambara nut intercrop has no significant effect on establishment, plant height, harvest index, days to 50 % podding and shelling percentage of bambara nuts. Results also showed that plant spacing and maize-bambara nut intercrop had significant effect on weight of dry pod, 100 seed weight and total grain yield of bambara nut. It is recommended that a wider plant spacing of 30 cm in a maize – bambara nut intercrop should be observed for meaningful yield in Yola.

Economic Analysis of Rice Production in Bende Local Government Area of Abia State, Nigeria

E. I. Offor — 2022-11-07

The study analyzed the economics of rice production in Bende Local Government area of Abia State, Nigeria. Specifically, the study addressed the following objectives: examine the socio economic characteristics of rice farmers, identify source of input to farmers, estimate cost and return of rice production, estimate determinants of rice production and identify problems that militates against rice production in the study area. The study used primary data source for the analysis. A multistage sampling techniques was used to sample for respondents. Data were analyzed using descriptive statistic, cost and return formulae and regression model. The result on socio-economics shows that the farmers were in their active stage with a mean age of 44 years, female farmers dominated rice farming, the farmers were literate with majority of the farmers attaining secondary education. On sources of input farmer association and personal sources were the major source of input for farmers in the study. On cost and return, the result shows that rice enterprise was viable. Among the factor that positively influenced rice production were farm size, chemical fertilizer, amount of credit and initial capital. Farmers identified pest and disease, and lack of access to credit as the major constrains to rice production in the study area. The study therefore recommends more farmers should join rice production since it is viable business and there is high demand for rice all over the country. More so, farmers should form cooperative society to increase their access to finances.

Effect of Moringa and Poultry Manure on Soil, Growth and Yield of (Amaranthus Cruentus) in Afikpo, Nigeria

E. O. Azu, Donatus — 2022-11-07

A Greenhouse trial was conducted in Research farm of Akanu Ibiam Federal Polytechnic, Nigeria, to investigate the effects of composted moringa leaves and poultry manure on soil chemical properties, growth and yield of amaranthus. Treatments consisted of three rates of composted moringa leaves (MC), (0, 1 and 2-ton ha^-1) and three rate of poultry manure (PM) (0, 1- and 2-ton ha^-1). The experiment was laid out in a Complete Randomized Design in a factorial pattern with three replications. The test soil was marginal in organic matter, inadequate in available P, acidic and general low in fertility. The results obtained showed that all rates of the manure significantly improved the soil nutrient status relative to control. All manure rates significantly increase the growth and yield of amaranthus. Relative to control, 2-ton ha^-1 MC and 2-ton ha^-1 PM increased number of leaves, plant height, and stem girth by 50%, 74.3% and 81% respectively. Generally, treatment combination of 2-ton ha^-1 MC and 2-ton ha^-1 PM gave the most appreciable increase in both soil nutrient and plant yield and it is therefore recommended for optimum and sustained amaranthus production in soils of Southeastern Nigeria.

Effects of Harvesting Stages, Packaging Materials and Storage Duration on Seed Quality of Tomato (Lycopersicon lycopersicon Mill) Varieties

T. S. Msaakpa — 2022-11-07

Three laboratory experiments on two varieties of tomato (Gianfranco Fuscello and Rio-grande) were conducted in 2017 and repeated in 2018.The experiments were aimed to study the effects of harvesting stages, packaging materials and storage duration on seed quality of tomato varieties. Two varieties of tomato, three harvesting stages, three packaging materials and three storage durations were used as treatments in a 2x3 and 2x3x3 factorial in Completely Randomized Design with four replications. Observations were recorded on germination counts (6 and 12 days after planting), post-emergence mortality, germination percentage, germination rate, germination index, seedling height, seedling fresh weight and seedling dry weight. Tomato fruits were harvested at three different stages as green matured, partially ripened matured and ripened matured at 40, 60, and 80 days after anthesis. Results were as follows; eighty days after anthesis recorded higher germination counts (6 and 12 days after planting), germination percentage, germination index, as compared to other harvesting stages; Aluminum foil bag was significantly higher in all the parameters observed; while the highest germination percentage was found after 3 months of storage. The study therefore recommends 80 days after anthesis as the best harvesting stage of tomato for optimum seed germination, growth and yield; also, aluminum foil is recommended as packaging material for farmers for adoption; Duration three and six months of storage are also recommended to farmers for better seed quality of tomato.

Effects of Poultry Manure and Rice Mill Waste on Some Physical Properties, pH and Organic Matter Content of Soils Under Three Land Use Types in Owerri North LGA, Imo State

P. C. Oguike — 2022-11-07

Changes in land use induce alterations in soil properties over time. A study was conducted in Owerri North Local Government Area of Imo State, Southeast Nigeria to assess changes in aggregate stability, water retention characteristics, bulk density (BD), organic matter (OM) and acidity (pH) of soils from different land use types amended with organic materials. The experiment was a 3x3 factorial laid out in a completely randomized design replicated thrice. The factors were oil palm plantation (PP), rubber plantation (RP) and arable land (AL) as factor A, and poultry manure (PM), rice mill waste (RMW) and a control (CT) as factor B. Analysis of variance (ANOVA) was performed and F-LSD_0.05 was used to compare the means. Rubber plantation (RP) recorded the highest mean weight diameter (MWD) in all treatments across land use, 3.00 mm in (CT), 4.93 mm in RMW, and 4.43 mm in PM) while AL recorded the lowest as observed in CT (1.60 mm), RMW (3.03 mm) and PM (2.53 mm). Arable land (AL) was most dispersed having clay dispersion index (CDI) of 53.90% (CT), 47.13% (RMW) and 45.77% (PM). Rice mill waste was better in reducing BD than PM and had the best reducing effect in AL (29.44%) than in PP (26.42%) and RP (11.11%). Field capacity (FC) increased by 15.24% when AL was amended with RMW and by 5.93% when amended with PM. Rice mill waste reduced acidity by increasing pH from 5.10 to 5.43 in PP, 5.40 to 5.66 in RP and 4.90 to 5.43 in AL. Organic matter (OM) was increased by 28.13%, 15.39% and 36.90% in PP, RP and AL, respectively, with application of RMW. The results indicated that the soil properties varied under the different land use types and they improved in response to the organic amendments. Therefore, the organic materials were effective in ameliorating the studied soils.

Gender-based Analysis of Rice Farmers’ Responses to Climate Change Adaptation Measures in South-East, Nigeria

O. J. Umeh — 2022-11-07

Impacts of climate change affect women and men differently. Therefore, assessing women and men responses to climate action is necessary in determining trend of innovation uptake for strengthening the resilience and coping strategies of the farmers to handle the challenges of a changing environment. This paper investigates comparative analysis of rice farmers’ responses to adaptation measures of climate change in South-East, Nigeria Multi-stage sampling procedure was used in selecting 360 respondents for the study. Data were obtained using structured questionnaire and analyzed using simple descriptive statistics and Z-test analysis. Results revealed that major responses exhibited by the farmers towards the use of listed adaptation measures were seeking for information based on observed changes ( = 3.0 males and ( = 3.0) females) and consulting fellow farmers for advice ( = 2.6 males and ( = 2.6). In addition, the male farmers also opt for value addition to the remaining crops ( = 2.5) while on the other hand, the female farmers prefer reverting to indigenous methods or self help methods ( = 2.5) in other to salvage their rice farms. The male farmers had higher mean score on positive perception of effects of climate change adaptation measures however; the female farmers had lower mean score. There is need therefore to provide timely information and coordinated capacity building to rice farmers along gender based identified needs and changes. Z-test comparative analysis show no significant difference (1.67**) in responses to adaptation measures between male and female farmers. However, the study calls for gender specific climate change menace coping capacity building for the farmers among others. This will address their individual vulnerabilities, increase farmers’ resilience towards weather variability and strengthen their ability to respond positively to implementation of adaptation measures in their rice farms.

Growth Rates and Determinants of Rubber Export in Nigeria

F. A. Nse-Nelson — 2022-11-07

The study analysed growth rates and determinants of rubber export in Nigeria. Time series data used for the study were collected from Central Bank of Nigeria (CBN) and National Bureau of Statistics (NBS). The data were analysed using exponential trend model, quadratic trend model, ordinary least square regression model and z-test. Findings from the study showed that time trend variable was a major factor in determining rubber export in the study period. The growth trend of rubber export in Nigeria per annum within the period under study (instantaneous rates of growth) was 4.15% and the rate of growth of rubber export in Nigeria (compound rates of growth) was 4. 23%. Results showed that there was stagnation in the growth rates of rubber export. Results further showed that there was a significant difference in the mean output quantity of rubber and exports within the period under review. From the regression model, it was observed that rubber export was positively influenced by output quantity of rubber, world price of rubber and producer price while it was negatively influenced by domestic utilization and nominal exchange rate. The study recommended the need to reassess the rubber export policy in Nigeria and to compliment it with such policies as farm support policies, output price incentives and non-price incentive policies.

Perception and Challenges of Small-Scale Farmers to Human Labour Access in North Central Nigeria

O. S. Akintobi — 2022-11-07

The study evaluated perception and challenges of small-scale farmers to human labour access in north central Nigeria. Multi-stage sampling technique was used for sample selection while questionnaire was used for data collection. A total of 1,750 farmers were randomly interviewed. Data were analyzed using descriptive statistics and two-way mixed factorial analysis of variance and mean separation was done at 5% probability level. Result shows that the farmers are aware of lack of access to labour. Mean separation showed Abuja (2.01) and Kwara State (1.72) having least access to labour. High cost of labour is the biggest challenge for farmers in accessing labour in north central Nigeria. Based on the findings, the research concluded that there is an ongoing decline in the availability of agricultural labour which will result in increased cost of production for the small-scale farmers. The study recommends that government should implement sector-specific policies that would protect the sectors most vulnerable from minimum wage shocks in order to boost their outputs and exports

Rainfall and Temperature trends in Samaru and Minjibir, Northern Guinea and Sudan Savannas of Nigeria

A. M. Yamusa — 2022-11-07

The changing trend of rainfall and temperature has been shown to vary in magnitudes in different regions of the globe and this has raised a lot of concerns with regards to the changing climate. This study investigated the rainfall and temperature trends from data collected from two research centers located in Samaru, Zaria (11º 11’N; 7º38’E and Minjibir, Kano (11º59’N; 8º 34’E), both in the northern Guinea and Sudan Savannas of Nigeria respectively. Mean annual rainfall from 1968 to 2017 was 1015.9 mm in Samaru and shows a trend of later onset and early cessation. In Minjibir, mean annual 744.5mm of rainfall (1975 -2017) whose onset was almost the same for the years studied, show a trend of early cessation. Standardized rainfall anomaly was experienced in 43% of years between late 1960’s to early 1990’s with varying degrees of drought from moderate to severe, while conditions of no drought to extreme wetness was observed from 2000’s till date with exception of few years. Similar trend was observed in Kano, with 39% of the years in the 1970’s to 1990’s with moderate to severe droughts, with no drought in the years from 2000’s till date. An increasing trend at the rate of 0.61^oC and 0.34^oC at Samaru and 0.67^oC and 0.76^oC at Kano for the maximum and minimum temperatures respectively was experienced, with mean minimum temperatures of 17.2 ºC in 1995 (the lowest recorded from 1968) and 20.9 ºC in 2013 in Samaru. Mean maximum temperatures were 29.5 ºC in 1970 and increased to 34.5 ºC in 2017 in Samaru, while the highest mean maximum temperature was 35.4 ºC recorded in 2011 for Minjibir. These results show the climatic cycles for rainfall and drought events and the increasing global temperatures, confirming a changing climate. Mitigation and adaptation strategies in these agroecological zones and the globe in general remain a crucial option to the consequences of climate change.

Utilization of Organic Farming Practices Among Rural Farming Households in Imo State, Nigeria

G. O. Mbah — 2022-11-07

The study examined utilization of organic farming practices among rural farming households in Imo State, Nigeria. It specifically, described socio-economic characteristics of the respondents; determined level of utilization of organic farming practices among rural farming households; and ascertained perceived effects of organic farming practices on arable crop farming among rural farming households in the study area. Purposive and multistage sampling procedures were used to select 120 respondents for the study. Data were collected using structured questionnaire and analysed using mean, percentages and multiple regression analysis. The findings showed that (65%) of the respondents were female and (92.5%) were farmers with mean age 47.0 years and mean farming experience of 11.1 years, Results indicated that the level of utilization of most of the organic farming practices was high with grand mean of 3.51 and showed positive perceived effect with grand mean of 4.23. Multiple regression result showed that coefficient of income and household size were statistically significant at 1% while coefficient of education was significant at 10% and positively related. The study concluded that most of the organic farming practices were highly utilized and recommended that there is need for NGOs and government to encourage organic farmers through procurement of loans for promoting and enhancing the full practice of organic agriculture.