The growth period, phenology, grain yield and gum content of two different guar ecotypes were studied in response to different sowing dates and plant densities. A two-year field experiment was conducted as a split-factorial in a randomized complete block design (RCBD) with three replicates in the research field of Tarbiat Modares University during 2016 and 2017 growing season. Main plots consisted of four sowing dates (May 21, June 4, June 21 and July 5 in 2016 and May 10, May 26, June 10 and June 26 in 2017), and subplots including three plant densities (13, 20 and 40 plants m-2) and two ecotypes (Pakistani and Indian). Based on findings, the phenological traits, plant height, grain yield and harvest index were significantly affected by plant density. The effect of ecotypes was statistically significant (p<0.05) on all traits except harvest index in the first year. Furthermore, the seed sowings on May 21 and May 26 with 13 plants m-2 led to highest grain yield (3004.8 and 2826.10 kg.ha-1 for two consecutive years). The high gum content (33.68 and 33.78% for two consecutive years) was also recorded for Pakistani ecotype while for gravity, Indian ecotype showed higher value in both crop years. By and large, the Pakistani ecotype showed better response compared to the Indian one in both years, especially in 1st and 2nd sowing dates.

中文翻译：

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半干旱地区播种期和种植密度对两种瓜尔豆(Cyamopsis tetragonoloba L.)生态型生长、产量和品质的影响。

研究了两种不同瓜尔胶生态型在不同播种期和植株密度下的生育期、物候、籽粒产量和胶质含量。在 Tarbiat Modares 大学的研究领域，在 2016 年和 2017 年的生长季节进行了为期两年的田间试验，作为随机完整区组设计 (RCBD) 中的分裂因子，进行了三个重复。主地块包括四个播种日期（2016 年的 5 月 21 日、6 月 4 日、6 月 21 日和 7 月 5 日和 2017 年的 5 月 10 日、5 月 26 日、6 月 10 日和 6 月 26 日），以及包括三个植物密度（13、20 和 40 株） m-2) 和两种生态型（巴基斯坦和印度）。根据研究结果，植物密度显着影响物候性状、株高、粮食产量和收获指数。生态型的影响具有统计学意义（p<0. 05）除第一年收获指数外的所有性状。此外，5 月 21 日和 5 月 26 日播种的 13 株 m-2 导致粮食产量最高（连续两年分别为 3004.8 和 2826.10 kg.ha-1）。巴基斯坦生态型的树胶含量也很高（连续两年为 33.68% 和 33.78%），而就重力而言，印度生态型在两个作物年度都显示出更高的值。总的来说，与印度生态型相比，巴基斯坦生态型在这两年中表现出更好的反应，尤其是在第 1 次和第 2 次播种期。印度生态型在两个作物年度都显示出更高的价值。总的来说，与印度生态型相比，巴基斯坦生态型在这两年中表现出更好的反应，尤其是在第 1 次和第 2 次播种期。印度生态型在两个作物年度都显示出更高的价值。总的来说，与印度生态型相比，巴基斯坦生态型在这两年中表现出更好的反应，尤其是在第 1 次和第 2 次播种期。