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Researcher Rana, N.
Advisor Solanki, N. S.
Source KrishiKosh-Indian National Agricultural Research System
Content type Text
Educational Degree Doctor of Philosophy (Ph.D.)
Publisher MPUAT
File Format PDF
Language English
Subject Domain (in DDC) Technology ♦ Agriculture & related technologies ♦ Animal husbandry
Subject Keyword Bio-regulators ♦ Mitigating Water Stress ♦ Normal ♦ Late Sown Wheat ♦ Bio-regulators For Mitigating Water Stress Under Normal and Late Sown Wheat ♦ Agronomy
Abstract A field experiment entitled “Bio-regulators for mitigating water stress under normal and late sown wheat†was conducted at Instructional Farm, Rajasthan College of Agriculture, Udaipur during two consecutive rabi seasons of 2013-14 and 2014-15 to find out the effect of water stress on phenology, growth and productivity of wheat (Triticum aestivum L.), to study the effect of water stress on biochemical and physiological changes in wheat and evaluation of bio-regulators for mitigating the adverse effect of water stress in wheat. Soil of experimental field was clay loam in texture with pH (8.0-8.1), low nitrogen (281.4-295.3 kg ha-1), medium phosphorus (18.4-19.5 kg ha-1) and high potassium (361.8-369.2 kg ha-1) and having good water holding capacity. The experiment consisted of 24 treatment combinations comprising six water stress (normal sowing with no stress, stress at tillering and tillering + 50 % heading and late sowing with no stress, stress at tillering and tillering + 50 % heading) and four levels of foliar spray of bio-regulators [water spray, salicylic acid (200 ppm), putrescine (10 ppm) and thiourea (1000 ppm)]. Wheat variety Raj-4037 was used as test crop. Combinations of these treatments were evaluated under split plot design, allocating water stress in main plots and foliar spray of bio-regulators treatment in sub plots with four replications. The results revealed that water stress at tillering + 50 % heading recorded significantly lower plant height (50 % heading and harvest), flag leaf area (50 % heading and 90 DAS), dry matter accumulation (leaves, stem and ear) at successive stages and number of tillers (at 60, 90 DAS and harvest) over no water stress under normal and late sowing conditions. Further, there was significant reduction in yield attributes viz., number of effective tillers (at 75 , 90, and harvest), number of spikes ear-1, number of grains ear-1 and 1000-grain weight with water stress at tillering + 50 * Ph.D. Research Scholar, Department of Agronomy, R.C.A., Udaipur (Rajasthan) ** Professor, Department of Agronomy, R.C.A., Udaipur (Rajasthan) % heading under normal and late sown crop. All growth and yield attributes were significantly reduced under late sown crop with no water stress as compared to normal sown crop. Grain yield, straw yield and biological yield were significantly decreased with water stress at tillering + 50 % heading stage over no water stress under normal and late sown conditions. The magnitude of reduction in grain yield with water stress at tillering + 50 % heading stage under normal and late sown crop was 15.3 and 15.4 per cent, respectively over no water stress. Further, significant reduction in grain yield was recorded under late sown crop with no water stress as compared to normal sown crop by 25.1 per cent. At 50 and 75 DAS, significant decrease in total chlorophyll and relative water content of leaves was recorded with water stress treatments under both normal and late sown crop. However, the extent of reduction was more under water stress at tillering + 50 % heading stage as compared to at tillering stage. Nutrient content (N, P and K) and uptake (N, P and K) were significantly reduced with water stress under both normal and late sown crop. Further, number of days required and growing degree days to attain different phenological stages of the crop decreased with water stress at tillering and tillering + 50 % heading under normal and late sowings. Similar trends were recorded with respect to heat use efficiency and consumptive use of water. However, water use efficiency was significantly increased with water stress at tillering and tillering + 50 % heading stage under both normal and late sown crop. Normal sown crop with water stress at tillering + 50 % heading stage recorded significantly lower net returns and B: C ratio by 15872 ha-1 and 0.36, respectively over no water stress ( 79520 ha-1 and 2.03). The lowest net returns and B: C ratio of ( 42332 ha-1) and 1.11 was recorded under late sown crop with water stress at tillering + 50 % heading stage. Foliar spray of salicylic acid and thiourea proved effective in improving growth and yield attributes. Grain, straw and biological yield were also significantly increased with foliar spray of salicylic acid (200 ppm) and thiourea (1000 ppm) over water spray. Foliar spray of salicylic acid (200 ppm) and thiourea (1000 ppm) gave significantly higher grain yield over water spray by 4.3 and 9.2 per cent respectively. Further, foliar spray of salicylic acid (200 ppm) and thiourea (1000 ppm) significantly increased proline content, relative water content, total chlorophyll content, nutrient (N and P) content and uptake (N, P and K) over water spray. Number days required to attain milking, dough and physiological maturity stages were significantly increased with foliar spray of salicylic acid (200 ppm) and thiourea (1000 ppm) over water spray. Similar trends were observed with respect to water use efficiency. The highest net returns and B:C ratio was obtained with foliar spray of thiourea ( 66813 ha-1 and 1.73) followed by of salicylic acid ( 63028 ha-1 and 1.65). Foliar spray of putrescine (10 ppm) fetched lower net returns ( 57609 ha- 1) and B:C ratio (1.42) as compare to water spray ( 58823 and 1.56).
Educational Use Research
Education Level UG and PG
Learning Resource Type Thesis
Publisher Place Udaipur
Size (in Bytes) 0.98 MB
Page Count 190