DEFOLIATION ENHANCES GREEN FORAGE PERFORMANCE BUT INHIBITS GRAIN YIELD IN BARLEY (HORDEUM VULGARE L.)

Abstract

SUMMARYTo evaluate the effects of defoliation on green forage performance and grain yield (GY) variation in barley, five barley genotypes were imposed on three levels of defoliation treatments over two consecutive growing seasons in this study. The results indicated that green forage yields were significantly improved by repeated defoliation. The traits of green forage quality, including the ratio of dry weight to fresh weight, crude ash and calcium content were improved, while crude protein and crude fat were reduced, and crude fiber and phosphorus contents appeared not to be influenced by repeated defoliation. Plant height (PH), GY and other yield components, grain number per spike and thousand kernel weight, were significantly reduced by defoliation over the two growing seasons, while internode length below spike was less affected. Reduction in spike length and the number of spikes per plant were identified in only one year. Correlation analysis revealed that only PH exhibited a positive correlation with GY. Effects of genotype, interaction between genotype and defoliation, and environments on changes of forage yield and quality and GY were also discussed. Our current work provides a feasible approach to select elite barley cultivars with optimal defoliation treatments for both forage and grain uses in barley breeding programme.

Breeding for purpose: Sole‐ and dual‐use barley

“…Despite relatively safer cutting timings applied in this study, there was an obvious grain yield reduction in the 2nd year due to later cutting as compared to the 1st year, which is in line with other findings (Royo et al., 1997; Salama, 2019). However, since barley is an autumn‐sown crop in south‐central China, the forage biomass is limited if cutting or grazing is conducted at an earlier vegetative stage during normal sowing period (Chen et al., 2016). Therefore, early sowing management could be applied, if conditions are allowed, to accelerate barley growth prior to jointing stage to harvest more forage yield with less grain yield penalty for DU production.…”

“…Barley ( Hordeum vulgare L.), serving as both grain and forage crops, is an important source of animal feed, which can provide high quality nutrients in livestock operations (Lyu et al., 2018; Royo et al., 1997; Vasilakoglou & Dhima, 2008). Barley is a winter crop in south‐central China, which has recently been used as forage specifically in winter and spring when other sources are not available (Chen et al., 2016). Generally, barley can be harvested at early‐dough stage as a sole‐use (SU) forage crop or as a dual‐use (DU) crop that is grazed by ruminants at early jointing stage for forage and subsequently harvested for grain (Royo et al., 1997; Salama, 2019).…”

“…The yield and quality of barley forage and grain are influenced by a number of factors such as seeding rate (Lithourgidis & Dordas, 2010; Salama, 2019), cutting stage (Chen et al., 2017; Guney et al., 2016; Royo et al., 1997), cutting frequency (Chen et al., 2016; Jebbouj & Yousfi, 2009), nitrogen fertilizer application (Malhi et al., 2014), and cropping system (Mosebi et al., 2018; Raskin et al., 2017; Sadeghpour et al., 2013). Delayed harvesting increased barley forage yield but reduced grain yield as well as forage quality (Salama, 2019; Seymour et al., 2015).…”

“…Our previous studies demonstrated significant differences in forage yield, quality, and grain yield among barley genotypes but no desired variety has been identified for improved forage and grain yield (Chen et al., 2016). The objectives of the present study were (a) to evaluate yield and quality differences among barley genotypes for both SU and DU and (b) to identify superior genotypes for both SU and DU production in south‐central China.…”