Water Relations, Growth, and Dry Matter Accumulation of Sorghum Under Post-Rainy Season Conditions
1979
Siva Kumar, M. V. K. | Seetharama, N. | Singh, Sardar | Bidinger, F. R.
Sorghum (Sorghum bicolor (L.) Moench) is one of the important crops grown under the residual soil moisture situation during the post-rainy (rabi) season in India. Field studies were conducted at the ICRISAT center on dee vertisols on the effects of water stress on the growth and dry matter accumulation of sorghum. Leaf water PQ tential and stomatal conductance were measured diurnally on four dates during the growing season. Irrigated sorghum crop exhibited higher stomatal conductance and higher leaf water potentials as compared to the nonirrigated sorghum. Higher transpiration rates observed in the case of the irrigated sorghum could be explained by the increased net radiation measured over the irrigated canopy. Lower leaves in the sorghum canopy showed lower stomatal conductance. Irrigated sorghum plants showed higher leaf area index and greater dry matter accumulation than those of the nonirrigated sorghum plants. There were significant differences in the final yield between the two treatments as reflected by less teritiary brancheslsecondaries, lower seed number/panicle and smaller seed size in the case of the nonirrigated sorghum. On a seasonal basis, the nonirrigated sorghum crop used 213 mm of water to produce 0.51 kg m⁻² of dry matter, whereas the irrigated sorghum extracted 321 mm of water to produce 0.93 kg m⁻² of dry matter.
显示更多 [+] 显示较少 [-]