Soybean Genotypic Response in Abbottabad

MATERIALS AND METHODS

The experiment was conducted during Kharif 2000 at Potato Research Centre, Abbottabad, Pakistan. Land preparation was done when soil was in water condition. Mixed fertilizer NPK @ 40-60-30 kg ha^-1 was applied at the seed bed preparation stage. The pure seed of soybean genotypes namely Wahab 93, Kharif 93, Clark, Flare, Pharoah, Tritan and Monarch were obtained from Pakistan Oilseed Development Board, Agricultural Research Institute, Tarnab, Peshawar. Experiment was planted on 4^th July in Randomized Complete Block Design with four replications. Each plot consisted of 5 rows; 5 meter long and 45 cm apart and having 5-7 cm intra plant spacing. All the agronomic practices were kept uniform. No insecticide or herbicide was used.

The data on the days to 50% flowering, days to maturity, plant height, 50 grains weight and seed yield was recorded. Crop was considered mature when 95% pods turned yellow. Seed yield was computed on kg ha^-1 basis, harvesting central two rows. Days to 50% flowering and maturity were adjudged on expert basis, while plant height and 50 grains weight were obtained from 15 plants at random form each replication. The results were statistically analyzed using MSTAT-C computer software.

Results and Discussion

Days to 50% flowering: Days counted from date of sowing to 50% flowering of these genotypes showed significant differences. Overall, cultivar Monarch took maximum number of days (53.00) to bear flowers. It was also significantly different from all other varieties (Table 1). Cultivar Wahab-93 took maximum number of days (41.00) for 50% flowering and was significantly different from other varieties. The differences in flowering could be attributed to differences among various genotypes. The results are in accordance with Thurlow and Johnson (1990).

Days to maturity: Genotypic response to maturity duration was significantly different for various varieties. Variety Tritan took maximum number of days (115.8) for maturation, while variety Flare took minimum number of days (95.25) to maturity (Table 1). Similar results with other varieties have been reported by Thurlow and Johnson (1990).

Table 1:	Average data of different soybean genotypes on days to 50% flowering, days to maturity, plant height (cm), 50-grains weight (gm) and yield ha-1 (kg)
Means followed by different letters in a column are significantly different from each other at P < 0.05.

Plant height (cm): The data for plant height (Table 1) revealed that variety Monarch was the tallest one (107.0 cm) and was significantly taller than all other varieties except Tritan. Variety Pharoah was most short statured (79.5 cm) and showed non significant differences with all other genotypes except Monarch. This shows that genetic potential Monarch for gaining height is higher than other genotypes. These results are in conformity with those obtained by Ehsanullah and Hatam (1989).

50 grains weight (gm): Data (Table 1) for 50 grains weight exhibited significant differences. It showed that genotype Clark had maximum 50 grains weight (20.0 gm), which was significantly higher than all other genotypes. Minimum 50 grains weight was recorded in variety Pharoah (14.45 gm), which was significantly lower than all other varieties except Flare and Tritan. Similar results have been reported by Zhang et al. (2000).

Yield per hectare (kg): The data (Table 1) analysis for yield ha^-1 in respect of various genotypes tested revealed significant differences. Variety Clark scored the highest yield (3489.0 kg ha^-1), which was significantly higher that all other varieties. Minimum yield (1222.0 kg ha^-1) was observed in genotype Kharif-93 which showed significant difference with all other varieties except Tritan and Monarch (Table 1). These results are in accordance with those obtained by Thurlow and Johnson (1990), Tritan et al. (1997) and Ablett et al. (2000).