Samireddypalle Anandan, Boukar Ousmane, Grings Elaine, Fatokun Christian A, Kodukula Prasad, Devulapalli Ravi, Okike Iheanacho, Blümmel Michael
International Livestock Research Institute Ibadan, Nigeria.
International Institute of Tropical Agriculture Kano, Nigeria.
Front Plant Sci. 2017 Jan 31;8:30. doi: 10.3389/fpls.2017.00030. eCollection 2017.
Cowpea is an important legume crop in Africa, valued highly for its grain and also haulms, which are a tradable commodity in fodder markets. Fodder market surveys in Northern Nigeria showed that groundnut haulms were priced higher than cowpea haulms, probably because of their superior nutritive value. The economic value of haulms has prompted cowpea breeders and livestock nutritionists to explore haulm fodder traits as additional selection and breeding criteria. Fifty cowpea genotypes cultivated across five locations in Nigeria in 2013 and 2014 were evaluated for food fodder traits. Significant ( < 0.05) genotypic dependent variations were observed in yields (kg/ha) of grains (537-1082) and haulms (1173-3368), though significant ( < 0.05) effects of location and year were observed. Grain and fodder yield had a tendency to be positively correlated ( = 0.26, = 0.07). Haulms were analyzed for nitrogen (N), fiber fractions, digestibility, and metabolizable energy content. Highly significant variations were observed in all genotypic and livestock nutrition traits, although location and year had significant effects. Trade-offs between grain yield and haulm fodder quality traits were largely absent and haulm acid detergent lignin and grain yield were even inversely correlated ( = -0.28, = 0.05), that is high grain yielders had decreased haulm lignin. However, haulm N and grain yield also tended to be negatively associated ( = -0.26, = 0.07). Haulm fodder quality traits and haulm yield were mostly positively correlated ( < 0.05). Broad sense heritabilities for grain and fodder yield were 0.50 and 0.29, respectively, while heritability for haulm fodder quality traits ranged from 0.61 to 0.67, providing opportunities for concomitant increase in grain yield and haulm fodder quality traits. Selection of the 10 highest ranking genotypes for grain yield, haulm yield, haulm N, and haulm organic matter digestibility showed selection groups overlapping, suggesting that multi-trait selection is feasible. Economical evaluation showed that choice of primary traits is context specific, highlighting the need for identifying and targeting appropriate genotypes to fit different production systems. Considering haulm quantity and quality as traits of economic value can increase overall plant value in mixed crop-livestock systems.
豇豆是非洲一种重要的豆类作物，其籽粒和豆秸都很受重视，豆秸是饲料市场上的一种可交易商品。尼日利亚北部的饲料市场调查显示，花生秸的价格高于豇豆秸，这可能是因为其营养价值更高。豆秸的经济价值促使豇豆育种者和家畜营养学家将豆秸饲料特性作为额外的选择和育种标准。对2013年和2014年在尼日利亚五个地点种植的50个豇豆基因型进行了食用和饲料特性评估。尽管观察到地点和年份有显著（<0.05）影响，但在籽粒产量（537 - 1082千克/公顷）和豆秸产量（1173 - 3368千克/公顷）方面观察到显著（<0.05）的基因型依赖性变异。籽粒产量和饲料产量有正相关趋势（r = 0.26，P = 0.07）。对豆秸进行了氮（N）、纤维组分、消化率和代谢能含量分析。在所有基因型和家畜营养特性方面都观察到高度显著的变异，尽管地点和年份有显著影响。籽粒产量和豆秸饲料品质性状之间基本不存在权衡，豆秸酸性洗涤木质素和籽粒产量甚至呈负相关（r = -0.28，P = 0.05），即高产籽粒的植株豆秸木质素含量降低。然而，豆秸氮含量和籽粒产量也往往呈负相关（r = -0.26，P = 0.07）。豆秸饲料品质性状和豆秸产量大多呈正相关（P < 0.05）。籽粒和饲料产量的广义遗传力分别为0.50和0.29，而豆秸饲料品质性状的遗传力范围为0.61至0.67，这为同时提高籽粒产量和豆秸饲料品质性状提供了机会。对籽粒产量、豆秸产量、豆秸氮含量和豆秸有机物质消化率排名最高的10个基因型的选择表明选择群体有重叠，这表明多性状选择是可行的。经济评估表明，主要性状的选择因具体情况而异，这突出了识别和针对适合不同生产系统的合适基因型的必要性。将豆秸数量和质量视为具有经济价值的性状可以提高混合作物 - 家畜系统中整个植株的价值。
