Abstract:
Field experiments was carried out in the high terraces of Dongla area, Northern State, Sudan for two seasons (2008/09 and 2009/10). The objective of this study was to study the effect of watering regimes of two cultivars of wheat.
The experimental design was split plot design with three replications. The irrigation treatments were water regimes every 19 days at certain stages of growth of wheat (a corroding to Zodak scales of wheat growth)as follows:
W1 = 1-20 days (germination + seedling development)
W2 = 21-39 days (tillering + stem elongation or jointing)
W3 = 40-59 days (booting +heading)
W4 = 60-79 days (flowering an anthesis + milk stage)
W5 = 80-99 days (dough + ripening), and W6 = control every 10 days. Irrigation treatments were included in the main plots, whereas, the cultivars were in the sub plots. The two cultivars were WadiEliel and Npta.
Parameters studie were plant height (cm), dry weight (gm) and number of tillers per squared meter every 24, 34, 44, 54, 64, 74, 84 and 94 days of growth. Yield components included spike/m, grain/spike spiklet/spike and 1000 seed weight. Grain yield (kg/ha), straw yield (kg/ha) harvest index and biomass (kg/ha) were also determined.
The results showed that Wadielneil cultivar had the highest weight compared with other cultivar (Npta) during all growth stages among the two seasons. And variation was significant (P=0.05) in 74, 84 and 94 days for growth in the first season; and 64, 74 and 94 days from growth of the second season. On the other hand, watering regimes obtained significant (P=0.05) effect in the second season at 54 and 74 days of growth at W4 and W6, respectively.
The dry weight affected significantly (P=0.05) by watering regimes at 24, 34, 44 and 84 days of the first season and 24, 64 and 94 days of the second season. Wadielneil cultivar had the heaviest dry weight than Npta in all readings for both seasons, but showed significant difference (P=0.05) at 24 and 64 days at the second season.
The watering regimes had significant difference (P=0.05) at tiller number/m at 84 of the first season and at 24, 44, 54 and 84 days at the second season. The cultivars had no significant effect on number of tillers except in 34, 74 and 94 days of the first season.
The interaction of watering regimes X cultivars had no clear effect for all parameters of growth except the W2V1 in the number of tillers per meter in the second season only. The results of the two seasons on yield components showed no significant effect in spike/m2, grain per spike, spikelet/spike and 1000 seed weight due to water regimes, but there were differences between cultivars. Npta showed the highest records for spike/m and spikelet/spike with significant effect in the first season. Meanwhile, Wadielneil had greater 1000-seed weight compared with Nebta. The average 1000-seed weight of Wadielneil (86.9, 37.9 gm) and Nepta between from (32.3-32.5 gm) for the two seasons, respectively with highly significant (P=0.01) difference at the first season. The variation of cultivars in the above yield components parameters referred to genetic variation.
In the first season, Npta showed higher grain yield than WadiElneil, which was 4540.4 and 3818 kg/ha, respectively. But in the second seasons Npta yield declined to 2609 kg/ha and WadiElienl increased significantly (P=0.01) to 4377.5 kg/ha. Also the interaction of watering intervals x cultivars obtained highly significant (P=0.01) difference at V1W2 with yield of 6281.6 kg/ha. Wadielneil had significant difference (P=0.05) in the first season and highly significant (P=0.01) in the second season for biomass and straw yield and W4 had the highest value for biomass and straw yield.