Cowpea Fodder Research Articles

Dual-purpose crops productivity and small-scale dairy farmers’ food security efforts toward climate variability and change in Benin

Dual-purpose cropping (sowing crops with the intention of both grazing them during vegetative growth and harvesting grain thereafter for household consumption) is certainly a promising way to address challenges face by small-scale dairy farmers in Benin due to climate variability and change. This study evaluated the impact of climate variability and change on dual-purpose crops productivity performances and nutritional values in Benin’s climatic regions. Four dual-purpose crops were studied. They are maize fodder, sorghum fodder, peanut fodder and cowpea fodder. The grain yield across various climate regions and years were assessed. Also fodders samples were analysed according to official methods of AOAC. The results showed that dual purposes crops yield were significantly affected particularly in some years in many regions of Benin by climate parameters variation. The variation of humidity had a negative effect on cereals dual-purpose crops production in Guinean region while the impacts of temperature and rainfall on dual purpose crops were higher in Sudanian region. The model for predicting the resistance of dual-purpose crops to climate variability and change revealed that The Annual Yield of Sorghum Grain was significantly influenced by humidity (P=0.0111), Rainfall (P=0.0374) and Weather station/Region (P=0.0493), as well as by the interaction between temperature and Grain Yield per Hectare (P=0.0423). The annual quantity of maize produced varied significantly with temperature (P=0.00154), humidity, Rainfall (P=0. 00792), Weather station/ Region (P=0.00362). The Annual Yield of Cowpea Grain production varied significantly with Temperature and Humidity (0.0205). Furthermore, temperature, humidity, year and Grain Yield per Hectare significantly affected the Annual Yield of Peanut Grain Produced. Nutritional values of the four studies dual-purpose crops were assessed. The energy values were 0.60 and 0.50 UFL/kg of Dry Matter respectively for sorghum-fodder and maize-fodder, the contents of digestible nitrogenous materials (MAD) were 1 and 0 g/kg of DM respectively for sorghum-fodder and maize-fodder. If the energy values were quite good for cereals fodder, the nitrogen values were very low. This study highlighted the nutritional advantage of leguminous fodders over cereal fodders.

Cowpea residue management effect on productivity of subsequent millet in a legume‐cereal crop rotation

AbstractGrowing cowpea (Vigna unguiculate (L) Walp) in rotation with millet (Pennisetum glaucum (L.) R. Br.) can increase millet productivity through biological nitrogen fixation. However, in Senegal, legume crop residues are generally removed for livestock feed, and little information exists on how burying the residue instead of removal affects the subsequent crop yield. This study assessed the productivity of cowpea varieties and evaluated prior cowpea residue management effect on grain and biomass yield of millet (Pennisetum glaucum (L.) R. Br) in rotation. Experiments were conducted in the National Center for Agronomic Research (CNRA) of Bambey in Senegal from 2020 to 2022. Treatments include 20 cowpea varieties, two fertilizer rates, and cowpea residue management practices (residue removal vs. burying) in a split‐split plot arrangement. Results showed that fertilizer and variety had significant effect on grain and fodder yields of cowpea. Cowpea fodder nutrient concentrations differed by variety, and the superior cowpea variety, 66‐35F, in nutrient concentration in this study had a 2.8‐0.45‐0.82% N‐P‐K. Applying fertilizer to previous cowpea crop increased millet grain yield by 63% compared to millet yield following previous non‐fertilized cowpea plots. Furthermore, incorporation of cowpea residue prior to millet planting increased millet yield by 40% compared with the removal of cowpea biomass in 2020 but had no significant effect in 2021. In general, the amount of cowpea biomass buried had significant positive relationship with millet grain yield. Across years, millet grain yield increased by 0.16 kg ha−1 for each kilogram per hectare increase in cowpea biomass buried prior to millet planting. Results showed that a minimum of 1500 kg ha−1 cowpea buried biomass was required to increase the probability of millet grain yield above 1000 kg ha−1. We concluded that the previous year's cowpea residue burial and fertilizer management improved productivity of the rotational millet crop.

Predicting Nutritional Quality of Dual-Purpose Cowpea Using NIRS and the Impacts of Crop Management

Cowpea fodder has been one of the favored livestock forages for centuries in sub-Saharan Africa, particularly in Senegal. However, little research has been conducted on quantifying the nutritional quality of cowpea fodder because of the costly wet chemistry analysis. The main objective of this study was to develop predictive equations for a sustainable quantification of the nutritional quality of dual-purpose cowpea fodder using near infrared spectroscopy (NIRS) and to investigate the influence of cropping system, fertilizer, genotype, and their interaction on biomass yield and cowpea forage nutritional value. In this study, 120 samples from a dual-purpose cowpea variety trial were used to develop NIRS equations to estimate forage quality parameters including concentrations of crude protein (CP), acid detergent fiber (ADF), neutral detergent fiber (NDF), calcium (Ca), phosphorus (P), potassium (K), and iron (Fe). Partial least squares (PLS) regression generated prediction equations using NIRS wavelength measurements, and reference wet chemistry analysis from calibration samples were developed. The PLS prediction equations for the different forage quality parameters had an R2 of calibration 0.94, 0.93, 0.88, 0.63, 0.69, 0.87, and 0.94 for CP, ADF, NDF, Ca, P, K, and Fe, respectively. Using these prediction equations, correlation of the predicted values of the calibration subset and the prediction test subset resulted in significant positive relationships, with R2 of 0.83, 0.74, 0.70, 0.63, 0.59, 0.75, and 0.83 for CP, ADF, NDF, Ca, P, K, and Fe, respectively. The corresponding RMSE of these relationships was 0.91, 2.68, 3.45, 0.23, 0.06, 0.11, and 100 for CP, ADF, NDF, Ca, P, K, and Fe, respectively. The range and mean concentrations of the calibration subset overlapped with that of the prediction subset for all parameters evaluated. Cross-validation procedures indicated good correlations between wet chemistry analysis and NIRS forage quality estimates. Results of the second experiment showed that the cropping system had no significant effect on cowpea forage yield and nutritive value. However, cowpea variety and fertilizer, both individually and their interaction, had a significant effect on fodder yield and cowpea forage quality. We conclude that the NIRS calibration equations developed can be used to accurately predict the cowpea forage quality parameters evaluated in this study.

Assessment of Nutrient Dynamics of Diversified Rice-wheat Cropping Sequences Under Integrated Farming System of Middle Igp

A field experiment was conducted with 10 crop sequences as treatments to find out nutrient dynamics and nutrient uptake pattern. This study was laid out in randomized block design with three replications. Among the different cropping sequence taken under study, sudan fodder- berseem- cowpea fodder recorded highest nitrogen (443.6 kg/ha), phosphorus (146.8 kg/ha) and potassium (306.3 kg/ha) uptake followed by cowpea fodder- berseem- maize fodder with 411, 105.9 and 274 kg/ha nitrogen, phosphorus and potassium, respectively. Both these crop sequences showed negative nitrogen balance in soil. Meanwhile potassium balance was negative for most of the sequences. However, high value rice- capsicum - vegetable cowpea registered lowest nitrogen (134.5 kg/ha) and potassium uptake (129.20 kg/ha) leading to a positive nitrogen and potassium balance. Bangladesh J. Bot. 51(3): 607-613, 2022 (September)

Bio-efficacy of nicosulfuron against mixed weed flora in maize and its residual effect on succeeding crops

A field study was conducted during Spring and rainy (Kharif) season of 2017 at N.E. Borlaug Crop Research Centre of G.B. Pant University of Agriculture and Technology, Pantnagar U.S. Nagar, Uttarakhand, India to evaluate the effective dose of nicosulfuron for weed control in maize while assessing its effect on growth and yield of maize along with its residual effect on succeeding pea and cowpea fodder. Eight treatments were tested which include: post-emergence application (PoE) of nicosulfuron at different doses (30, 36, 42 and 50 g/ha), tembotrione 120 g/ha PoE, pre-emergence application (PE) of atrazine 1000 g/ha, hand weeding twice at 20 and 40 days after seeding (DAS) and weedy check. The weed community during both the seasons in the experimental area consisted of, grassy weeds: Phalaris minor, Eleusine indica, Digitaria sanguinalis, Echinochloa colona and Panicum maximum, broad-leaved weeds (BLW): Trianthema monogyna, Chenopodium album, Phyllanthus niruri, Parthenium hysterophorus and Mallugo stricta and a sedge Cyperus rotundus. Nicosulfuron at 50 g/ha resulted in 50-100% weed control, depending on the weed species. Nicosulfuron at 50 and 42 g/ha were equally effective in increasing grain yield of maize when compared with tembotrione and was found superior over atrazine during both the season. No phytotoxic symptoms on maize and no residual effect on succeeding pea and cowpea fodder crop were observed, at any doses of nicosulfuron. Hence, nicosulfuron at 42 g/ha PoE may be safely used for effective weed management and improved yield of maize.

Impact of Biochar and Hydrogel Amendments on Hydrophysical Properties of Sandy Soil and Cowpea Yield (VignaUnguiculata L.) Under Different Water Regimes

South Mediterranean countries including Egypt and Tunisia are characterized by vast lands withuncultivated sandy soils. These soils have poor hydrophysical-bio-chemical properties that are being reclaimeddue to population growth and the need to increase food supply. Furthermore, there is high production of crop and orchard residues from agricultural activities thatlead to harmful effects to theenvironment. Therefore, converting these residues to biochar and theiruse as amendments with sandy soils could improve water retention. This research investigated the effect of three soil amendments: - biochar (50 g/plant and 100 g/plant), hydrogel (2.7 g/plant) and their mixtures (hydro-char) (50 g biochar and 2.7 g hydrogel) on some hydrophysical properties. The properties included soil water constants, pore size distribution and void ratios on yield parameters of the cowpea fodder crop under two irrigation levels (100 and 75% on base of ETc) evaluated under field experiment.The results showed that higher water content at field capacity (FC) and available water content (AW) was observed with the use of 50 and 100g/plant biochar followed by hydro-char combinations. Data revealed that higher values of drainable pores (DP) were recorded after 2.7 g hydrogel, and 100 g biochar; storage pores (SP) after 2.7 hydrogel and 100g biochar, and100g biochar; whereas none useful pores were recorded after2.7 hydrogel under 75 and 100% irrigation regimes. Positivecorrelations were recorded between FC drainable poresDP, storage pores SP, total porosity TP, and void ratio with r-values of 0.544*, 0.983**, 0.805**; 0.814**, respectively.Also, thebiological yield exhibited positive correlations with water holding capacity (WHC), FC, AW, SP,TP, andvoid ratio with r-values of 0.797**, 0.835**, 0.864**, 0.879**, 0.628** and 0.631**, respectively. Yield variables increasedhigher in75% than in 100%irrigation regimes. It wasconcluded that the ability of biochar to enhance the hydrophysical properties of sandy soils is highly dependent on thebiochar characteristics and its application rates. Furthermore, biochar applications can increase water retentionin sandy soils.

Diversification of Rice–wheat Cropping System Improves Growth, Productivity and Energetics of Rice in the Indo-Gangetic Plains of India

Rice–wheat cropping system plays a vital role in ensuring food security of India. However, the long-term sustainability of the system is often questioned due to several problems associated with it. Diversification of the rice–wheat cropping system with suitable crops could be a possible solution. Thus, a field experiment consisting of ten rice-based cropping sequences was conducted in a randomized block design with three replications at Banaras Hindu University, Varanasi, India, for two consecutive years to study the effects of crop diversification on rice performance. The effect of crop diversification on rice was found to be significant only during the second year of experimentation. Results showed that rice–berseem–cowpea fodder followed by rice–potato–green gram sequence recorded highest growth, yield, nutrients uptake, protein yield, carbohydrates yield, economics and energetics of rice. Rice–berseem–cowpea fodder sequence recorded significantly higher number of panicle m−2 (16%), grain yield (13.9%), straw yield (13.6%), total N, P, K uptake (17.2, 21.7, 17%, respectively), protein yield (14.6%) and carbohydrate equivalent yield (13.9%) over rice–wheat cropping sequence. In addition to above, rice–berseem–cowpea fodder sequence also proved significantly superior to rice–wheat cropping sequence and recorded higher gross returns (13.9%), net returns (46.6%), net energy (15.9%), energy productivity (13.8%) and energy intensity (13.9%). Rice–berseem–cowpea fodder and rice–potato–green gram were found the most suitable cropping sequence to diversify rice–wheat cropping system in the Indo-Gangetic plain for better performance of rice.

Nutritional portfolio of maize and cowpea fodder under various intercropping ratio and balanced nitrogen fertilization

Cereal–legume mixture may be a viable option to improve forage yield and quality. Furthermore, nitrogen requirement may also varying according to proportion of legume component. Therefore, the present study was carried out to evaluate the effect of different intercropping ratios and nitrogen levels on productivity and nutritional quality of fodder maize (Zea mays L.) and Cowpea (Vigna unguiculata L.). The experiment was laid out in split plot arrangement with three intercropping row ratios of maize: cowpea (1:1, 2:1 and 1:2, respectively) in main plot and five nitrogen levels (0, 30, 60, 90 and 120 kg N/ha) in sub plot. Highest total green fodder, protein and ash yield in 2:1 ratio whereas maximum ether yield was reported in 1:2 intercropping ratio of maize and cowpea. However, the maximum crude protein, ether extract, ash content and lowest NDF, ADF and ADL of maize and cowpea, respectively were obtained under 1:2 intercropping ratio of maize and cowpea. Among N levels, highest total green fodder, crude protein, ether and ash yield and as well as their content in green forage of maize and cowpea were recorded with the use of 120 kg N/ha. However, cowpea responded significantly upto 60 kg N/ha only. The lowest NDF, ADF and ADL of maize and cowpea were found when these crops fertilized with 120 Kg N/ha. A significant interaction between intercropping ratios and N levels was reported in terms of yield. Thus, it can be concluded that nitrogen rates 90, 120 and 60 kg/ha found suitable to achieve maximum fodder yield in 1:1, 2:1 and 1:2 (maize: cowpea) ratios, respectively.

Nutritive value of cowpea fodder cultivars and their effect on nutrients intake, digestibility and nitrogen balance in sheep

Three cowpea fodder varieties (BL-1, BL-2 and BL-4) developed by IGFRI were evaluated against check Kohinoor for their nutritional attributes by in vitro and in vivo means. Varieties were grown under identical agronomic practices in Kharif 2016 and animal feeding was started at flower initiation stage. For feeding trial, 20 growing sheep (mean body weight 19.85±0.45 kg) were randomly distributed to 4 varieties (Kohinoor, BL-1, BL-2 and BL- 4) with 5 animals to each. After 3 weeks of feeding, a digestion cum- metabolism trial was conducted to assess the nutrients intake, digestibility and nitrogen balance in sheep. The cowpea fodder varieties CP, NDF and lignin contents differed and values ranged between 22.23–23.41, 50.54–55.10 and 8.48–10.76%, respectively. Protein and carbohydrate fractions of cowpea varieties were similar except the NSC (% DM) and CC (% CHO) which were lower and higher, respectively in BL-2. Cowpea varieties energy values as TDN, DE, NEL, NEM and NEG were identical. In vitro gas and methane production (ml/g DM) was lower from Kohinoor (86.57 and 10.67) and BL-2 (90.79 and 11.40) than BL-1 (104.83 and 13.96) and BL-4 (98.86 and 13.08), respectively. Short chain fatty acids, partition factor and efficiency for microbial production differed significantly amongst the cowpea varieties. Sheep DM, CP and ME intake (% body wt and g/kg W0.75) was comparable on evaluated cowpea varieties. Digestibility of DM, OM and CP in sheep was similar on cowpea varieties; however, NDF and ADF digestibility tended to be lower of BL-4 (63.88 and 61.70%) than BL-2. Sheep nitrogen balance was identical on all the cowpea varieties and ranged between 16.92–18.32 g/d. Cowpea varieties DCP and DE contents were similar and ranged between 18.36– 20.30% and 13.63–14.72 kjoules/g DM, respectively. Results showed that nutritive value of cowpea varieties differed significantly in terms of CP, NDF, NSC%DM, fermentation pattern, and cell wall (NDF and ADF) digestibility.

English

Cowpea is a major food legume crop in the Sahel with tolerance to drought and to the nutrients-leached acid sandy soils of this region. However, the existing cowpea varieties grown by farmers are low yielding and pest sensitive which make them unsuitable to satisfy farmer’s needs. The objective of this study was to identify high-yielding cowpea varieties which are well adapted to the Sahelian ecosystem. Eight dual-purpose cowpea varieties from various sources were tested with and without insects control in Niger during two cropping seasons (2005 and 2007). In 2005, a relatively wet year, KVX 745-11-P and four other varieties (ISV 20, ISV 40, ISV 128 and IT98D-1399) gave highest grain yields ranging from 1220 to 1521 kg ha-1. In the dry year (2007), the highest grain yield was recorded with ISV 128. There were also significant differences in forage yield between varieties in both the wet and dry year. Application of insecticide increased cowpea grain yields significantly. Cowpea produced without insect control (spray) resulted in high grain yields losses and increased cowpea fodder yields in both years. KVX 745-11-P was the most sensitive variety to insects whereas IT98D 1399 seemed to be relatively the most insect tolerant variety. There were no significant differences between varieties in most forage quality parameters. These results provide the possibility of a potential extension of dual-cowpea varieties for improved food security in the Sahel. Keywords: Dual purpose cowpea, grain yield, fodder quality, sahel

Yield and nutrient content of hydroponics cowpea sprouts at various stages of growth

Hydroponics cowpea (Vigna unguiculata) (NB-4) sprouts were produced daily for 15 days in a hydroponics chamber (greenhouse) equipped with automatic sprayer irrigation of tap water. Cowpea (NB-4) with seed rate of 2.54 kg/m2 with replicates of 15 was soaked in tap water individually for 4 h.The seeds were strained and spread in the greenhouse trays. Inside the greenhouse, each replicate was allowed to grow for 9 d, after which it was harvested. The fresh yield (kg/kg seed) of the hydroponically sprouted cowpea (NB-4) increased with the advancement of growing period and remained similar and highest from day 6 (6.34) to 9 (6.63) growing period. Simultaneously, with the growth of the hydroponics cowpea sprouts, the DM content (%) decreased and remained similar and lowest from day 8 (6.91) to day 9 (6.49) growing period. The CP(%) of the hydroponics cowpea fodder was lowest on the day 1 (22.30), then increased and remained similar during seventh (30.10) to ninth (31.23) day sprouting period. The EE content increased and remained similar during day 5 (2.31%) to 8 (2.47%) of sprouting, however, it was highest on day 9 (3.22) of growth. During the growth period of the hydroponics cowpea sprouts, the CF(%) and NFE(%) had an increasing and decreasing trend and was highest and lowest, respectively, on day 9 (21.59 and 38.59). There was an increasing trend in the TA and AIA content of the hydroponics cowpea sprouts with the advancement of the growth period, which was lowest on day 1 (3.99) and highest (5.38) on day 9. It can be concluded that based on the yield and different nutrient contents, cowpea (NB-4) can be sprouted hydroponically for 6–9 days to use as feed supplement for dairy animals.

Effect of phosphorus and zinc nutrition on growth and yield of fodder cowpea

An experiment consisting of four phosphorus levels (0, 40, 60 and 80 kg/ha P2O5) and five zinc levels (0, 10, 20, 30 and 40 kg/ha ZnSO4) was laid out in randomized block design in factorial mode to find out the effect on yield and quality of fodder cowpea [Vigna Unguiculata (L.)Walp.]. Growth parameters viz. plant height, number of leaves, number of branches, leaf length, leaf width and leaf stem ratio were improved with the application of 60 kg/ha P2O5 and 20 kg/ha ZnSO4. Application of 60 kg/ha phosphorus recorded 27.64 t/ha yield, which was 7.50 and 55.6 % higher than 40 kg/ha and no phosphorus application, respectively. Application of zinc in the form of ZnSO4 @ 20 kg/ha increased significantly the green fodder yield (25.89 t/ha). Interaction effect of phosphorus and zinc application was found significant with respect to green fodder, dry matter yield and nutrient uptake. Yield, phosphorus and zinc uptake in cowpea fodder were showing declining trend at combination of application rate more than 60 kg/ha P2O5 and 20 kg/ha ZnSO4.

Unravelling the causes of variability in crop yields and treatment responses for better tailoring of options for sustainable intensification in southern Mali

Options that contribute to sustainable intensification offer an avenue to improve crop yields and farmers’ livelihoods. However, insufficient knowledge on the performance of various options in the context of smallholder farm systems impedes local adaptation and adoption. Therefore, together with farmers in southern Mali we tested a range of options for sustainable intensification including intensification of cereal (maize and sorghum) and legume (groundnut, soyabean and cowpea) sole crops and cereal-legume intercropping during three years on on-farm trials. There was huge variability among fields in crop yields of unamended control plots: maize yielded from 0.20 to 5.24tha−1, sorghum from 0 to 3.53tha−1, groundnut from 0.10 to 1.16tha−1, soyabean from 0 to 2.48tha−1 and cowpea from 0 to 1.02tha−1. This variability was partly explained by (i) soil type and water holding capacity, (ii) previous crop, its management and the nutrient carry-over and (iii) inter-annual weather variability. Farmers recognized three soil types: gravelly soils, sandy soils and black soils. Yields were very poor on gravelly soils and two to three times greater (depending on the crop) on black soils. Yields were also poor at the end of the typical crop rotation, i.e., after sorghum and millet, and 1.3–1.7 times greater (depending on the crop) after the fertilized crops maize and cotton. We diagnosed a number of cases of technology failure where no improvement in yield was observed with hybrid varieties of maize and sorghum and rhizobial inoculation of soyabean. Regardless of soil type and previous crop, mineral fertilizer improved yields by 34–126% depending on the crop. Targeting options to a given soil type and/or place in the rotation enhanced their agronomic performance: (i) the biomass production of the cowpea fodder variety was doubled on black soils compared with gravelly soils, (ii) the additive maize/cowpea intercropping option after cotton or maize resulted in an average overall LER of 1.47, no maize grain penalty, and 1.38tha−1 more cowpea fodder production compared with sole maize. Soil type and position in the rotation, two indicators easy to assess by farmers and extension workers, allowed the identification of specific niches for enhanced agronomic performance of legume sole cropping and/or intercropping.

Effect of Preceding Intercrops inBTCotton on The Productivity of Succeeding Wheat Crop and Total System Productivity

A field experiment was conducted to study the effect of different intercrops and row ratio on the growth, yield and quality of hybrid Bt cotton and effect of preceding intercrops in Bt cotton on the productivity of succeeding wheat crop and total system productivity. The results showed that different yield attributes, grain and straw yield of wheat were not significantly affected by different intercrops, though numerically higher wheat yield was obtained, where it was sown after legume intercrops viz. Bt cotton + cowpea fodder or Bt cotton + summer moong intercropping systems, as compared to that after sole Bt cotton and Bt cotton intercropped with other non legume intercrops viz. maize fodder, Bajra fodder and long melon etc. During 2010–11 crop season, all the intercropping systems except Bt cotton+ Bajra fodder-wheat and Bt cotton + long melon-wheat system recorded significantly higher total system productivity as compared to sole Bt cotton-wheat system. However, during 2011–12 crop season, intercropping systems like Bt cotton + maize fodder-wheat and Bt cotton + cowpea fodder-wheat system recorded significantly higher total system productivity as compared to sole Bt cotton-wheat system, Bt cotton + summer moong-wheat, Bt cotton + Bajra fodder-wheat and Bt cotton+ long melon-wheat systems. The land use efficiency in Bt cotton-wheat and Bt cotton based intercropping system-wheat varied from 93 to 96 percent as compared to 59–63 percent in sole crop-wheat based systems. With the introduction of legumes as sole or intercrop component, soil N status either improved or it remained same as initial status of the soil.

Nutrient Changes with the Growth of Hydroponics Cowpea (Vigna unguiculata) Sprouts

Hydroponics cowpea (Vigna unguiculata; DU-3) sprouts were produced daily for a period of 15 days in a hydroponics chamber (greenhouse) equipped with automatic sprayer of tap water. Cowpea with seed rate of 2.54 kg/m2 with replicates of 15 were soaked in tap water individually for 4 h. Then, the seeds were strained and spread in the greenhouse trays. Inside the greenhouse, each replicate was allowed to grow up to 6 days after which it was harvested. The fresh yield (kg/kg seed) of hydroponically sprouted cowpea increased while that DM yield decreased (P<0.05) with the advancement of growing period and respective values remained highest and lowest at 6th day (6.75 and 9.32 kg) of growing period. The CP% of the hydroponics cowpea fodder was the lowest (P<0.05) on 1st day (21.04), then increased and was the highest on 6th day (27.16%) day of sprouting period. The EE content increased and was the highest on 5th (1.69%) to 6th day (1.77%) of sprouting. During growth period of the hydroponics cowpea sprouts, the CF content increased and NFE level decreased. There was an increasing trend in total ash content of the hydroponics cowpea sprouts with the advancement of the growth period which was the lowest on 1st day (3.40) and the highest (4.44) on 6th day, however, the AIA content was not affected with the advancement of growing period. It could be concluded that cowpea (Vigna unguiculata; DU-3) could be sprouted hydroponically for 6 days to use as feed supplement for dairy animals, however, in vivo trials are required.

English

Integrated crop-livestock is advocated to be very promising in boosting food productivity and soil fertility in Nigeria owing to its numerous synergistic benefits as outlined in this review. Particularly, the system will be very suitable in the savannah regions of the country where livestock production is predominant. Although integrated crop-livestock farming has been in existence in these regions, it is typically cereal based-livestock system resulting in perennial depletion of soil fertility. Introduction of legumes into the system to form cereal-legume-livestock system can function as a key integrating factor through improvement of soil fertility, provision of healthy protein in the human diet and fodder for livestock consumption. This paper therefore, aimed to review the benefits of introduction of legumes like cowpea into the long existing cereal based livestock farming in Nigeria, particularly in the savannah regions of the country in order to boost food security and income of the farmers. The review showed that incorporation of cowpea into the system will in greater measure increase the overall food productivity, ensures sustainability of the soil fertility and substantially improves the income of the farmers in the country. &nbsp; Key words: Cowpea fodder, soil fertility, food security, nutrient cycling.

Boron profile in common feedstuffs used in tropical livestock systems

In the scenario of increased reports on boron (B) supplementation in animal diets for beneficial effects, there is inadequate information on B content of animal feeds. The present study was carried out to quantify the level of B in animal feeds commonly used in tropical feeding systems. Samples of a total of 225 feeds were procured. The feed samples were oven dried, ground to 1mm size and wet digested, filtered using Whatman filter paper (no 42) and volume made up to 100ml by deionized water. Boron (B) content was estimated using inductively coupled plasma optical emission spectroscopy (ICP-OES). The level of B in fibrous feeds (n=83) was higher than in concentrate feeds (n=120) and unconventional feeds (n=22). The range of B content among the feed samples analyzed (n=225) showed a wide range from rice bran to cowpea fodder (0.69–59.1mg/kg). The spatial distribution of B indicates that most feed samples analyzed showed B content lower than 20mg/kg with mean and median of 17.7±0.96 and 14.4, respectively. It is evident from the present study that appreciable quantity of B is detected in all the major categories of feedstuffs which was comparable to the levels of essential trace elements like copper and zinc. These findings would facilitate in assessing the supplementary value of tropical feeds for boron.

Effect of Phosphorus and Zinc Application on Nutritional Characteristics of Fodder Cowpea (Vigna unguiculata)

An experiment consisting of four phosphorus levels (0, 40, 60 and 80 kg/ha P2O5) and five zinc levels (0, 10, 20, 30 and 40 kg/ha ZnSO4) was laid out in factorial randomized block design to find out the effect on yield and nutritive value of fodder cowpea (Vigna unguiculata). Application of 60 kg/ha phosphorus recorded 27.64 t/ha yield which was 7.50 and 55.6% higher than 40 kg/ha and no phosphorus application, respectively. Application of Zn in the form of ZnSO4 @ 20 kg/ha increased (P<0.05) the green fodder yield (25.89 t/ha). The successive increase in P level from 0 to 60 kg P2O5/ha enhanced CP level significantly (P<0.05) from 15.07 to 17.97%. Zinc application also increased CP content from 15.23 to 17.56% with increase in ZnSO4 level from 0 to 20 kg/ha. The content of NDF and ADF were not influenced due to application of Zn and P. The interaction effects of P and Zn were found to be significant (P<0.05) with respect to P and Zn concentration. P and Zn content in cowpea fodder showed declining trend at application rate more than 60 kg/ha P2O5 and 20 kg/ha ZnSO4. Therefore, a combination of 60 kg/ha P2O5 and 20 kg/ha ZnSO4 could be applied to obtain better yield and nutritive value of fodder cowpea.

Field evaluation of neem seed extract for the control of major pests of cowpea in northern Ghana

Field studies were conducted at the Experimental Farm of the Savanna Agricultural Research Institute (SARI), Nyankpala, northern Ghana, during the 2006 cropping season to evaluate the effect of aqueous neem (Azadirachta indica A. Juss) seed extract at 5, 10, 15 and 20 per cent on Aphis craccivora Koch., Megalurothrips sjostedti Tryb., Maruca vitrata Fab., and a complex of pod and seed-sucking bugs of cowpea (Vigna unguiculata L. Walpers), as well as their effect on the grain and fodder yields of the crop. The results showed that the incidence and abundance of all the target insect pests were significantly affected by the neem extract treatments. Cowpea grain yield was significantly higher in all the neem-treated plots than in the control. The 15 per cent neem seed extract treatment proved as effective as that of the 20 per cent in increasing the grain yield of the cowpea crop. However, none of the neem treatments was as effective as the synthetic insecticide (Karate) in cowpea grain yield. However, grain quality for the 15 and 20 per cent treatments was similar to that for the Karate treatment. Cowpea fodder yield was found to decrease with increasing concentration of the neem extract. Benefit-cost analysis for the grain and fodder yields showed that the 15 and 5 per cent neem extract treatments, respectively, had the best benefit-cost ratios. Therefore, the 15 per cent neem seed extract is recommended for use in controlling the major field insect pests of cowpea for maximum grain yield in the Guinea savanna agroecological zone of Ghana. However, for situations in which the grower is strapped for cash or neem seeds are inadequate, the 5 or 10 per cent extract may be used. The 5 per cent neem seed extract is recommended for dual-purpose cowpea cultivars for maximum returns on grain and fodder yield.

Effect of incorporation of crop residues and organic manures on adsorption/desorption and bio-availability of phosphate

Transformations of applied phosphorus (P) to unavailable residual soil P is the major cause of limited P supply in most of the P-deficient soils. The effect of the incorporation of crop residues (rice straw [RS] and wheat straw [WS]) and organic manures (farmyard manure [FYM] and green manure [GM]) on P release in soil and its bio-availability to various summer and winter crops was investigated in laboratory and screen house experiments. Surface (0–0.15 m) soil samples collected after 32 years of differential fertilization to maize–wheat–cowpea fodder crop rotation, were examined for adsorption/desorption behavior of P, after incubating with organics of varying C:P ratios. Incorporation of crop residues increased P adsorption maxima as well as resistance to P release in soils. Increased buffering capacities in crop residue-incorporated treatments decreased P desorption in soil, whereas the incorporation of organic manures decreased P sorption, maximum buffering capacity (MBC), bonding energy, and increased P concentration in soil solution. Although the incorporation of crop residues decreased P release in soil its bio-availability in the soil–plant system was crop-specific and varied with the time of incorporation of organics. Raya showed increased P uptake with incorporation of both RS and WS, whereas in the case of berseem increased P uptake occurred only with wheat straw. Phosphorus uptake in rice, maize, and soybean decreased with the incorporation of both RS and WS. Incorporation of crop residues 1 day before the sowing of summer crops decreased P uptake, whereas incorporation 3 weeks prior to the sowing of winter crops improved P bio-availability. Incorporation of organic manures with a narrow C:P ratio, however, improved P uptake in all the crops under investigation, in both the seasons. The results thus emphasized that adsorption parameters calculated from the examination of soil samples should not be used independently for making fertilizer P recommendations. Crop effects (root exudates) and their interaction with P reaction products in soil and synchronization in P release from organics and crop uptake need to be considered to understand the virtual behavior of P bio-availability in the soil–plant system.