Photosynthetic Activity Of Rice Cultivars And Formation Of High Grain Yields

2017 ◽  
Vol 3 (5) ◽  
pp. 34-43
Author(s):  
K. N. ZHAYLYBAY
Keyword(s):  
Photosynthetic Activity ◽  
Rice Cultivars ◽  
Grain Yields

Interference Durations of Bearded Sprangletop (Leptochloa fascicularis) in Rice (Oryza sativa)

Weed Science ◽  
1994 ◽  
Vol 42 (2) ◽  
pp. 180-183 ◽  
Author(s):  
V. Frank Carey ◽  
Roy J. Smith ◽  
Ronald E. Talbert
Keyword(s):  
Oryza Sativa ◽  
Plant Height ◽  
Dry Weight ◽  
Rice Cultivars ◽  
Grain Yields

Effects of bearded sprangletop interference durations on Lemont and Newbonnet rice cultivars were studied. Interference durations of 63, 70, and 130 d after rice emergence reduced Lemont grain yields 11, 21, and 50%, respectively, and lowered Newbonnet grain yields 11, 13, and 37%, respectively. Interference durations of 21 to 56 d after emergence did not reduce grain yields of either cultivar. Bearded sprangletop grown in Lemont rice produced more biomass than that in Newbonnet. Season-long interference reduced plant height and straw dry weight of Lemont more than that of Newbonnet.

Density and Spatial Interference of Barnyardgrass (Echinochloa crus-galli) with Rice (Oryza sativa)

Weed Science ◽  
1991 ◽  
Vol 39 (2) ◽  
pp. 163-168 ◽  
Author(s):  
Larry G. Stauber ◽  
Roy J. Smith ◽  
Ronald E. Talbert
Keyword(s):  
Grain Yield ◽  
Yield Reduction ◽  
Rice Cultivars ◽  
Straw Yield ◽  
Grain Yields ◽  
Group 4 ◽  
Plant Groups ◽  
Plant Group ◽  
Rice Yields ◽  
Spatial Interference

Density and spatial interference of barnyardgrass with ‘Lemont’ and ‘Newbonnet’ rice cultivars was investigated in 1987 and 1988. Barnyardgrass reduced grain yield of Lemont, a semidwarf cultivar, more than Newbonnet, a short-statured cultivar. Linear regression indicated that season-long interference of barnyardgrass at 1 to 20 plants m–2reduced grain yields of Lemont and Newbonnet by 301 and 257 kg ha–1per barnyardgrass plant, respectively. Grain yields of Lemont and Newbonnet were reduced by barnyardgrass densities to 40 plants m–2but were not affected further at densities ≥40 plants m–2. Barnyardgrass reduced straw yield of Lemont more than of Newbonnet. Although barnyardgrass culms m–2and straw yield increased as weed density increased, the weed produced more culms per plant at 2 and 5 m–2than at 20 to 80 m–2. In a spatial interference experiment, Lemont grain yield reduction averaged 21% when plants were grown within 0 to 25 cm of a barnyardgrass plant group (group = 4 plants per 140 cm2). However, rice yields were not reduced when barnyardgrass plant groups were 25 to 50 or 50 to 100 cm away. Additional treatments included two barnyardgrass groups spaced 20, 40, 80, or 100 cm apart When Lemont grew between barnyardgrass groups spaced 20 or 40 cm apart, grain yields were reduced 40 and 27%, respectively, compared with weed-free rice. However, Lemont yield was not reduced when rice plants grew between weed plant groups spaced 100 cm apart.

Competition of Barnyardgrass by Rice Cultivars

Weed Science ◽  
1974 ◽  
Vol 22 (5) ◽  
pp. 423-426 ◽  
Author(s):  
R. J. Smith
Keyword(s):  
Oryza Sativa ◽  
Weed Competition ◽  
Rice Cultivars ◽  
Grain Yields

Competitiveness of three high-yielding, lodging-resistant rice (Oryza sativaL.) cultivars with barnyardgrass [Echinochloa crus-galli(L.) Beauv.] was compared during 3 years at Stuttgart, Arkansas. ‘Starbonnet,’ ‘Nova 66,’ and ‘Bluebelle,’ which matured in 145, 135, and 125 days, respectively, competed with barnyardgrass for periods ranging from 10 days after crop emergence to all season. ‘Starbonnet’ was the most competitive and ‘Bluebelle’ was the least. Barnyardgrass competition for 10 or 20 days did not reduce grain yields of any cultivar. Weed competition for 40 days or longer reduced yields of ‘Nova 66’ and ‘Bluebelle,’ and competition for 60 days or longer lowered yields of ‘Starbonnet.’ As the period for maturity increased, each cultivar competed more effectively with barnyardgrass.

scholarly journals Estimating the yield stability of heat-tolerant rice genotypes under various heat conditions across reproductive stages: a 5-year case study

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chao Wu ◽  
Kehui Cui ◽  
Qian Li ◽  
Liuyong Li ◽  
Wencheng Wang ◽  
...  
Keyword(s):  
Heat Stress ◽  
Grain Yield ◽  
Grain Filling ◽  
Yield Stability ◽  
Reproductive Stage ◽  
Rice Cultivars ◽  
Grain Yields ◽  
Rice Genotypes ◽  
Heat Tolerant ◽  
Heat Events

AbstractHeat events during the reproductive stages of rice plants induce great yield losses. Cultivating heat-tolerant varieties is a promising strategy for guaranteeing grain security under global warming scenarios. Most heat-tolerant rice genotypes were identified under heat during the flowering stage, but it is unclear whether these currently screened heat-tolerant rice genotypes maintain stable high grain yields when heat stress occurs during the other reproductive stages. In the present study, two notable heat-tolerant rice cultivars, Nagina22 and Shanyou63, and one typical heat-sensitive cultivar, Liangyoupeijiu, were evaluated for their yield response and yield stability under heat treatments during the panicle initiation, flowering, and grain filling stages during 2010–2014. Our results revealed that rice cultivars respond differently to heat stress during different reproductive stages. Nagina22 was the most tolerant to heat stress during the flowering and grain filling stages but was susceptible during panicle initiation; Shanyou63 was the most tolerant to heat stress during panicle initiation and grain filling and was moderately tolerant to heat stress during the flowering stages. Genotype and genotype-by-environment interaction biplot yield analysis revealed that Shanyou63 exhibited the highest stability in high grain yield, followed by Nagina22, and Liangyoupeijiu exhibited stable low grain yield when experiencing heat stress across the three reproductive stages. Our results indicate that the heat tolerance of different rice cultivars depends on the reproductive stage during which heat stress occurs, and the effects manifest as reductions in grain yields and seed setting rates. Future efforts to develop heat-tolerant varieties should strive to breed varieties that are comprehensively tolerant to heat stress during any reproductive stage to cope with the unpredictable occurrence of future heat events.

QUALITATIVE STABILITY OF WINTER WHEAT VARIETIES AT DIFFERENT LOCATIONS

2000 ◽  
Vol 48 (2) ◽  
pp. 191-195
Author(s):  
C. Kondora ◽  
M. Szabó ◽  
A. Máté ◽  
G. Szabó
Keyword(s):  
Quality Control ◽  
Winter Wheat ◽  
Evaluation Method ◽  
Wheat Varieties ◽  
Local Conditions ◽  
Grain Yields ◽  
Baking Quality ◽  
Small Plot ◽  
High Yielding Varieties ◽  
Winter Wheat Varieties

Owing to the significant differences in the adaptability of state-registered varieties, those which can adapt well to the local conditions should be given preference. There are several high-yielding varieties available in Hungary with excellent agronomic properties, good adaptability and satisfactory baking quality. This study was conducted to analyse the adaptability of 34 state-registered winter wheat varieties tested in the small plot trials of the National Institute for Agricultural Quality Control (NIAQC) at 5–9 locations between 1994 and 1997 based on their gluten quantity and farinographic index. For the comparison of the varieties the evaluation method of Eberhart and Russell (1966) was applied as modified by Bedő and Balla (1977). The qualitative stability and adaptability values of the varieties differ from the adaptability and stability values calculated from the grain yields. Some winter wheat varieties have good qualitative adaptability and stability, while others have special adaptability and poor qualitative stability, but the majority of the varieties do not belong to these groups.

On the Mechanism of Action of Easily Oxidizable Phenols on Photosynthetic Activity of Algae

2006 ◽  
Vol 42 (4) ◽  
pp. 82-92
Author(s):  
A. I. Sakevich ◽  
V. D. Romanenko ◽  
O. M. Usenko
Keyword(s):  
Mechanism Of Action ◽  
Photosynthetic Activity
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