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Evaluation of some Bread Wheat Cultivars Productivity as Affected by Sowing Dates and Water Stress in Semi-arid Region  [PDF]
Eman I. El-Sarag,Ryad I.M. Ismaeil
Asian Journal of Crop Science , 2013,
Abstract: Agriculture is inherently sensitive to weather and climate especially water supply and heat changes. Adaptation of an appropriate economic management strategy is one of the likely decisions to cope with the impacts of climate changes. The effect of the potential impact of three sowing dates; first sowing date (16th November, FSD), second sowing date (1st December, SSD) and third sowing date (16th December, TSD) on two wheat cultivars (Giza 168 and Sakha 93) under three levels of water stress (irrigation every: 10; 15 and 20 days) was studied at the Farm of Environmental Agricultural Sciences Faculty, El-Arish, during two winter seasons (2009/2010; 2010/2011). Results showed that the Second Sowing Date (SSD) gave superiority of wheat grain yield and most of its components, in response to increasing heat temperature at anthesis stage. Most of growth characters, grain yield and its components of Sakha 93 cultivar were greater than Giza 168 under both stressed and non-stressed conditions; this cultivar could be adapted to heat and water stress more than the other one in relation to its genetic stability under unfavorable conditions and its positive response to late sowing date. Water Consumptive Use (WCU) means by Sakha 93 was higher than those of Giza 168 under all water stress levels; superiority was recorded for 10 day interval.
Yield and Yield Components of Various Wheat Cultivars as Affected by Different Sowing Dates  [PDF]
Khurram Shahzad,Jehan Bakht,Wajid Ali Shah,Muhammad Shafi
Asian Journal of Plant Sciences , 2002,
Abstract: An experiment was conducted to study the yield and yield components of various wheat cultivars as affected by different sowing dates. Statistical analysis of the data revealed that different date of sowing and varieties had a significant effect on days to maturity, 1000 grain weight, grains spike -1, grain yield, biological yield and harvest index. While plant height, days to maturity, grains -1, 1000 grain weight, grain yield and biological yield was significantly affected by interaction between different sowing dates and varieties. Mean value of the data revealed that plant height (106 cm), grains -1, 1000 grain weight (75.20 g), grain yield (3611.11 kg ha -1) and biological yield (10370.00 kg ha -1) was maximum in those plots which were sown on November 1st when compared with other sowing dates. Similarly variety tatara-96 recorded maximum plant height, grains -1, 1000 grain weight, grain yield and harvest index when compared with other varieties under study.
Influence of Different Sowing Dates on the Phenology and Accumulated Heat Units in Wheat
S.A. Haider,M.Z. Alam,M.F. Alam,N.K. Paul
Journal of Biological Sciences , 2003,
Abstract: A field investigation was carried out to study the influence of sowing dates on phenology and accumulated heat units of four cultivars of bread wheat (Triticum aestivum L.) at different phenological stages over two growing seasons. There were two sowing dates: early and late. The late sown plants had significantly shorter phenological stages and lower growing day degree than the early sown plants in all the four cultivars. Cultivars Akbar was found to be early and C 306 was found to be late maturing. Akbar had the lowest and C 306 had the highest growing degree days during all the phenological stages under each irrigation regimes. Heliothermal units also showed more or less the same trends. The phenothermal indices and heat use efficiency were found to be higher in the early sown plants than the late sown plants.
The Effect of Different Sowing Dates on Growing Periods, Yield and Yield Components of Some Bread Wheat (Triticum aestivum L.) Cultivars Grown in the East-Mediterranean Region of Turkey  [PDF]
Tevrican Dokuyucu,Aydin Akkaya,Didem Yigitoglu
Journal of Agronomy , 2004,
Abstract: The aim of this research was to determine the effect of different sowing dates on growing period, yield and some yield components of three bread wheat (Triticum aestivum L.) cultivars grown Kahramanmaras, in the East-Mediterranean region of Turkey. Experiment was carried out in a split-plot on randomized complete block design with four replications, between the year 1997-1999. Seven planting dates were planned with the first on 9th October and the others followed at about 15 day intervals. Two cultivars (Seri-82, Dogankent-1 and Panda) were the main plots and 7 different sowing dates were the subplots. According to the results of two years, sowing dates had significant effect on vegetative period (VP), grain filling period (GFP), days to maturity (DM), head number m-2 (HN m-2), 1000-grain weight (1000-GW) and grain yield (GY). Grain yields obtained from the first five sowing dates were not significantly different. Consequently, the period from first week of November to middle of December could be concluded as optimum sowing period for maximum grain yield for the region.
Response of Wheat Varieties to Sowing Dates  [PDF]
M. Aslam,Manzoor Hussain,M. Akhtar,M.S. Cheema
Journal of Agronomy , 2003,
Abstract: The study was conducted to evaluate the appropriate sowing time of newly evolved wheat varieties/cultivars under Bahawalpur conditions. The study included 6 sowing dates started form Ist November up to 15th January of year 1999-2000 to 2000-2001 with equal intervals of fifteen days and five varieties/cultivars viz., 2236, 2098, 2219 punjnad-1 with inqlab, 91 as standard one. Regardless of varieties/cultivars the best results were obtained when wheat was sown after Ist and before 15th November of year 1999 to 2000. However wheat variety punjnad-1 gave significantly higher weights in a wide range of sowing period i.e., Ist to 30th November. The highest mean grain yield of 5315 kg ha-1 was obtained when crop was sown on 15th November (D2) followed by 5268 kg ha-1 for sowing on Ist November (D1).
Responses of Wheat Genotypes as Affected by Different Sowing Dates
F. Aslani,M.R. Mehrvar
Asian Journal of Agricultural Sciences , 2012,
Abstract: A field experiment was conducted Seed and Plant Improvement Institute, Karaj (Iran) for two seasons, 2007-08 and 2008-09, on farmer’s fields to investigate the effect of two sowing dates; optimum sowing date (1st November) and late sowing date (20th November) on yield and yield components of eight wheat genotypes. The results showed that the optimum sowing produced higher grain and biomass yields, 1000- grain weight, Spike per square meter compared to late sowing. Between grain yield and traits of biological yield, 1000- grain weight and grain per square meter were correlated positively.
Effect of Sowing Dates on the Yield and Yield Components of Different Wheat Varieties  [PDF]
Wajid Ali Shah,Jehan Bakht,Tehseen Ullah,Abdul Wahab Khan
Journal of Agronomy , 2006,
Abstract: To study the effect of sowing dates on the yield and yield components of different wheat varieties an experiment was conducted at Malakandhar Research Farm of NWFP Agriculture University Peshawar during 1999-2000. Statistical analysis of the data revealed that different dates sowing and varieties had a significant effect on emergences m-2, number of productive tillers m-2, number of unproductive tillers m-2, spike length, grain yield and biological yield. While number of unproductive tillers m-2, days to heading and biological yield were significantly affected by interaction between different sowing dates and varieties. Mean value of the data revealed that emergence m-2 (179). spike length (11.33 cm). grain yield (3611.11 kg ha-1) and biological yield (10370.00 kg ha-1) was maximum in those plots which were sown on November 1st when compared with other sowing dates. Similarly variety Tatara-96 recorded maximum emergence m-2, days to heading, number of productive tillers m-2, spike length and grain yield when compared with other varieties under study.
Infrared Warming Reduced Winter Wheat Yields and Some Physiological Parameters, Which Were Mitigated by Irrigation and Worsened by Delayed Sowing  [PDF]
Shibo Fang, Hua Su, Wei Liu, Kaiyan Tan, Sanxue Ren
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0067518
Abstract: Winter wheat has a central role in ensuring the food security and welfare of 1.3 billion people in China. Extensive previous studies have concluded that winter wheat yields would decrease with higher temperatures, owing to warming-induced soil drying or shortening of phenophase. Temperature in China is predicted to increase by 1–5°C by 2100, which may greatly impact plant production and cause other negative effects. We performed a manipulative field experiment, creating diverse growth regimes for wheat by infrared radiation (IR) warming day and night, including IR warming only (DW), IR warming + delayed sowing dates (DS), IR warming + increased irrigation (IW), and a control (CK). The results show that IR warming increased daily average wheat canopy and soil temperatures by 2.0°C and 2.3°C, respectively. DW was associated with an advanced maturity of 10 days and yield reduction of 8.2%. IR-warming effects on the photosynthetic apparatus of wheat varied with season as well as significant differences were found in the booting stage. DS represented a worsened situation, lowering yield per plant by 16.4%, with a significant decline in aboveground biomass and functional leaf area. Wheat under DS showed double-peak patterns of diurnal gas exchange during booting stages and, consequently, lower photosynthetic capacity with high transpiration for cooling. Significantly lower actual water use efficiency and intrinsic water use efficiency from jointing to anthesis stages were also found under DS. However, IW had no significant difference from CK, irrespective of yield and photosynthesis. Therefore, we concluded that delayed sowing date may not be a good choice for winter wheat, whereas a thoroughly-watered wheat agroecosystem should be promoted in the context of global warming.
Effect of Different Sowing Dates on Cotton (Gossypium hirsutum L.) Cultivars  [PDF]
Mahmood-ul-Hassan,Muhammad Nasrullah,Muhammad Zaffar Iqbal,Taj Muhammad
Asian Journal of Plant Sciences , 2003,
Abstract: An experiment was conducted to assess the effect of sowing date on two cotton varieties MNH552 and MNH554 grown on Ist April, 15th April, Ist. May, 15th May, Ist. June, 15th June, Ist. July and 15th July during 1998 and 1999 under Multan conditions. 15th May and Ist June sown cotton displayed significantly maximum seed cotton yield of 2998 and 2883 kg ha-1 in 1998 and 4027 and 3894 kg ha-1 respectively in 1999 as compared to 595 and 253 kg ha-1 (1998) and 1269 and 223 kg ha-1 (1999) from crop sown on Ist and 15th July respectively. The increase in both sowing dates in seed cotton yield was associated with boll weight and bolls per plant. On average of two years data 15th May produced highest seed cotton yield of 3513 kg ha-1, whereas the lowest figure was 238 kg ha-1 (15th July). Comparing varietal performance MNH552 (2310 kg ha-1) yielded higher as compared to MNH554 (2288 kg ha-1). However two cultivars declined the yield in late planting.
Analysis of self-fertilization and meiotic behavior of eleven Brazilian triticale cultivars at two sowing dates
Guerra, Divanilde;Pacheco, Marcelo Teixeira;Federizzi, Luiz Carlos;
Crop Breeding and Applied Biotechnology , 2011, DOI: 10.1590/S1984-70332011000200003
Abstract: eleven brazilian hexaploid triticale cultivars (2n = 6x = 42), from three breeding programs, were evaluated for their ability of self-fertilization in 2006 and for meiotic behavior, meiotic index and pollen viability at two sowing dates in 2007. high potential of self-fertilization was observed, with values up to 89.52 %. many irregularities were found in the meiotic analysis, such as the presence of univalents, laggard chromosomes and micronuclei in tetrads, which compromised both meiotic behavior and meiotic index. at the first sowing date, more suitable for normal plant development, overall mean values of 52.68 % for normal cells and 64.95 % for meiotic index were observed. at the second sowing date, less appropriate for the crop, overall means of 52.23 % for normal cells and 58.24 % for meiotic index were obtained. despite all the irregularities, considerable pollen viability was observed, reaching overall means of 92.08 % and 91.07 % for the first and second sowing dates, respectively.
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