Quality seed production of range grasses ? A major constraint in revitalizing tropical pastures

Abstract

Only 4% of India’s geographical area of 326.82 Mha is under pastures. Socioeconomic and ecological consequences of land degradation are affecting 85 Mha of rangelands/grasslands. To provide sufficient milk for the ever-growing population, current milk production of 128 Mt must increase to 160 Mt by 2020. To make this possible, an additional 825 Mt of green fodder is required. Increasing the area producing green fodder is difficult because of severe competition from food crops. Revitalizing the denuded grasslands is the most plausible means for improving the availability of green fodder. This needs mission mode programs with participation of the people. One impediment to increased green fodder production is limited availability of good quality seed. In India only 25−30% of the required seed is available for sowing cultivated fodder and 20% and 15% for range grasses and legumes, respectively (Anon. 2011). Forage seed production encounters several problems, namely: poor seed setting; extreme climatic conditions; seed shattering and non-synchronization in maturity; and the presence of empty seeds. Empty seeds with partially developed embryos and poor nutrient reserves fail to germinate. The standard germination percentage of most tropical grasses is around 20−30 percent. Several studies have been conducted to enhance germination by treating with GA3 or KNO3 or by other means of dormancy removal. However, the major reason for the low germination percentage is formation of ‘false’ seeds (dry floral parts without fully developed seeds). Wobus and Weber (1999) emphasized the role of hormones in combination with other seed metabolites, including sugar, in seed maturation. Understanding reproductive biology and harvest scheduling are also important for enhancing formation of pure, germinating seeds. Hence, the present study was con-