Evaluation of Morphological Characteristics and Forage Biomass Yield of Five Selected Wheat Cultivars for Ruminant Livestock Nutrition in Northern Pakistan

Abstract

P akistan is the fourth largest milk producing country in the world, and milk and milk products play an important role in national Gross Domestic Products (GDP), particularly in livelihood and economy of rural population. However, there is still an increasing demand for milk and milk products, Abstract | This research study evaluated the genetic variation in forage biomass yield, morphological characteristic, forage nutritional value and digestibility among five selected wheat genotypes. The five cultivars, namely, Pir Sabaq (PS)-15, Bakhtawar-92, PS-2000, National Agriculture Research Council (NARC)-11 and Zam-04 were grown in 12 replicate plots (6 m × 10 m), that were blocked in three fields according to Randomized Complete Block Design. Uniform field preparation, irrigation, weeds control and standard agronomic practices were applied to all plots. For forage yield, morphological and quality evaluation, samples were collected from randomly selected one-meter long strip of two consecutive rows of each plot at feekes stages 7 to 8, when the second last leaf was visible. The collected samples were immediately weighed, and 10 plants were subsampled from each sample for morphological evaluation. Ten plants were weighed and separated into stem and leaves portion, subsequently weighed and analysed for dry matter (DM) content. The remaining samples were air dried, ground and analysed for chemical composition and in vitro digestibility (IVDMD) and in vitro gas production (IVGP). The results revealed large variability (P < 0.001) in DM yield, ranging from 1943 to 2763 kg/ha. There was also greater variability (P ˂ 0.001) in morphological characteristics among the wheat cultivars. The percentage of leaves varied from 0.33 to 0.45% and leaf to stem ratio varied from 0.47 to 0.84. There was also marked variation (P ˂ 0.001) in the plant height, ranging from 68.7 to 79.3 cm. The chemical composition showed large range (P ˂ 0.001) among the five wheat cultivars, the ash content varied from 6.01 to 7.90%, crude protein (CP) from 8.71 to 12.40% and crude fat (CFat) from 1.02 to 3.26%. The neutral detergent fibre (NDF) from 43.2 to 44.7%. The IVDMD varied from 48.4 to 58.9% and IVGP varied from 110 to 172 mL/g organic matter. Among the five wheat cultivars Bakhtawar-92 had maximum DM yield (2747 kg/ha), proportion of leaves (45%), CP (12.4%), IVDMD (58.9%) and IVGP (172 mL/g organic matter), and minimum portion of stem (55%) and NDF (43.2%), and thus supported greater yield of high quality wheat fodder. Other cultivars which combined similar desirable characteristic were ranked in order of merit as PS-15, PS-2000, NARC-11 and Zam-04.