ROLE OF AMINO ACIDS IN IMPROVING GROWTH, YIELD AND PHYSIOLOGICAL PARAMETERS OF SOME EGYPTIAN CLOVER CULTIVARS

The lack of green forage of good quality is considered the main constraints that contribute to the lack of livestock development. An experiment was performed at Sakha Agricultural Research Station Farm, Kafr El-Sheikh Governorate, Egypt, to study the role of spraying commercial amino acids (g-plus) and pure tryptophan on forage yield and chemical composition of three Egyptian clover cultivars during the two successive winter seasons 2019/2020 and 2020/2021.  The experiment was laid out in a strip-plot design with three replications. The main plots were occupied by amino acids treatments i.e. spray with water (control), spray with g-plus (5cm/l water) and spray with tryptophan at two concentration (200 and 400 mg/l). While sub-plots contained three cultivars of berseem; Helaly, Serw1 and Giza 6. The results showed that, the maximum total fresh forage yield, total dry forage yield, average of plant height, number of stem per 0.25 m2, fresh leaf/stem percent and dry leaf/stem percent were obtained for variety Helaly spraying by amino acid g-plus (5cm/l water). Also, the obtained results showed that, foliar spraying of amino acids caused significant increase of most physiological characters in comparison to the control. The highest values of chlorophyll content, relative water content (RWC %), protein % and NPK% were obtained with spraying g-plus. Concerning, the cultivars effects showed a wide range of variation in their productivity where, Helaly was the highest values of the most physiological parameters as well as yield and yield components. The interaction effects of foliar spraying of amino acids and cultivars showed that, Helaly treated with g-plus (5cm/l) gave the highest values of growth and physiological parameters.