Evaluation of Guar Genotypes (Cluster Beans) Characteristics Under Rainfed and Supplementary Irrigation Conditions

In order to investigate the yield and yield components of Guar (Cyamopsis tetragonoloba L.) genotypes to supplementary irrigation in rainfed conditions, a two-year study has been conducted in the form of split strip plots based on a randomized complete block design with three replications at stations Shirvan, Kohnehkand and Mohammadabad research stations in North Khorasan during 2019-2020 cropping years. The main factor includes irrigation levels at three levels: rainfed, two irrigations (after planting and filling seed time), and three irrigations (after planting, pod formation and filling seed), with the second factor being guar genotypes at four levels. The three Genotypes include RGC-1077, RGC-1036, RGC-1025, and Chabahar local population. Results of the combined analysis show that there has been no significant difference between genotype except in the number of days to flowering. On the other hand, the effect of supplementary irrigation treatment on yield characteristics compared to rainfed conditions is significant, though there has not been any significant difference between two and three times of supplementary irrigation. Guar seed yield in the first and second years in the Ashkhaneh region (750.5 and 219.1 kg.ha-1) outperforms Bojnourd and Shirvan. The highest grain yield (590 kg.ha-1) is obtained in the first year from double irrigation and in the second year (271.51 kg.ha-1) from three irrigations. Among the experimental genotypes, the highest grain yield belongs to the RGC-1025 genotype. In general, guar culture of the RGC-1025 genotype can be recommended in the Ashkhaneh area..