Response of two sunflower hybrids to planting dates and densities

2003 ◽  
Vol 51 (1) ◽  
pp. 25-35 ◽  
Author(s):  
A. Y. Allam ◽  
G. R. El-Nagar ◽  
A. H. Galal
Keyword(s):  
Seed Yield ◽  
Significant Influence ◽  
Plant Density ◽  
Growth Traits ◽  
Sowing Date ◽  
Planting Date ◽  
Oil Yield ◽  
Planting Density ◽  
Planting Dates ◽  
Head Diameter

This investigation was carried out at the Experimental Farm of Assiut University during the summers of 2000 and 2001 to study the responses of two sunflower hybrids (Vidoc and Euroflora) to planting dates (May 1st, June 1st and July 1st) and planting densities (55,533, 83,300 and 166,600 plants/ha). The results indicated that the two varieties differed highly significantly in all studied traits except oil yield/ha. The highest seed yield (3.64 t/ha) was obtained with the variety Vidoc. In addition, the results revealed that the planting date exerted a highly significant influence on all vegetative growth traits along with yield and its components. Increasing plant density increased the seed and oil yield/ha. By contrast, the stem diameter, head diameter, 100-seed weight and seed yield/plant decreased with increasing plant density. The interaction between varieties and plant density had a highly significant effect on head diameter. The greatest head diameter (20.06 cm) was recorded for the variety Vidoc planted at lower density. Concerning the interaction between planting density and planting date, the highest seed yield (4.47 t/ha) was obtained from dense plants at the early sowing date, and the highest oil % (45.32) at the late planting date and the lowest plant density. The second order interaction exerted a highly significant influence on stem and head diameter in addition to seed yield/plant, where the highest value (78.13 g/plant) was obtained with the variety Vidoc planted on May 1st at the lowest plant density.

scholarly journals Effective Seed Yield and Flowering Synchrony of Parents of CIMMYT Three-Way-Cross Tropical Maize Hybrids

Agriculture ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 161
Author(s):  
Alberto A. Chassaigne-Ricciulli ◽  
Leopoldo E. Mendoza-Onofre ◽  
Leobigildo Córdova-Téllez ◽  
Aquiles Carballo-Carballo ◽  
Félix M. San Vicente-García ◽  
...  
Keyword(s):  
Seed Production ◽  
Seed Yield ◽  
Grain Filling ◽  
Sowing Date ◽  
Planting Density ◽  
Planting Dates ◽  
Flowering Synchrony ◽  
Sowing Dates ◽  
Grain Filling Period ◽  
Hybrid Maize

Genotype, environmental temperature, and agronomic management of parents influence seed yield in three-way cross hybrid maize seed production. The objective of this research was to generate information on the seed production of six three-way cross hybrids and their progenitors, adapted to tropical lowlands. Data on days to—and duration of—flowering, distance to spike and stigmas, and seed yield of five female single crosses and five male inbred lines were recorded for different combinations of four planting densities and four sowing dates in Mexico. The effect of planting density was not significant. The male inbred line T10 was the earliest and highest seed yield and T31 the latest, occupying second place in yield. The single crosses T32/T10 and T13/T14 were the earliest and had the highest effective seed yield. At the earliest sowing date, the females were later in their flowering, accumulated fewer growing degree days (GDD), and obtained higher yields since the grain-filling period coincided with hot days and cool nights. To achieve greater floral synchronization and therefore greater production of hybrid seed, differential planting dates for parents are recommended based on information from the accumulated GDD of each parent. The three-way cross hybrids were classified according to the expected seed yield of the females and the complexity in the synchronization of flowering of their parents.

Nitrogen Demand of Cut Chrysanthemums in Relation to Shoot Height and Planting Date

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 523c-523
Author(s):  
Siegfried Zerche
Keyword(s):  
Dry Matter ◽  
Plant Density ◽  
Plant Biomass ◽  
N Uptake ◽  
Planting Date ◽  
Dry Matter Accumulation ◽  
Planting Dates ◽  
Shoot Height ◽  
Climate Conditions ◽  
Growing Period

Refined nutrient delivery systems are important for environmentally friendly production of cut flowers in both soil and hydroponic culture. They have to be closely orientated at the actual nutrient demand. To solve current problems, express analysis and nutrient uptake models have been developed in horticulture. However, the necessity of relatively laborious analysis or estimation of model input parameters have prevented their commercial use up to now. For this reason, we studied relationships between easily determinable parameters of plant biomass structure as shoot height, plant density and dry matter production as well as amount of nitrogen removal of hydroponically grown year-round cut chrysanthemums. In four experiments (planting dates 5.11.91; 25.3.92; 4.1.93; 1.7.93) with cultivar `Puma white' and a fixed plant density of 64 m2, shoots were harvested every 14 days from planting until flowering, with dry matter, internal N concentration and shoot height being measured. For each planting date, N uptake (y) was closely (r2 = 0.94; 0.93; 0.84; 0.93, respectively) related to shoot height (x) at the time of cutting and could be characterized by the equation y = a * × b. In the soilless cultivation system, dry matter concentrations of N remained constant over the whole growing period, indicating non-limiting nitrogen supply. In agreement with constant internal N concentrations, N uptake was linearly related (r2 = 0.94 to 0.99) to dry matter accumulation. It is concluded that shoot height is a useful parameter to include in a simple model of N uptake. However, in consideration of fluctuating greenhouse climate conditions needs more sophisticated approaches including processes such as water uptake and photosynthetically active radiation.

scholarly journals Effect of planting dates on the yield of broccoli genotypes

2015 ◽  
Vol 40 (3) ◽  
pp. 465-478
Author(s):  
MA Hafiz ◽  
A Biswas ◽  
M Zakaria ◽  
J Hassan ◽  
NA Ivy
Keyword(s):  
Plant Height ◽  
Total Yield ◽  
Planting Date ◽  
Flower Head ◽  
Planting Dates ◽  
Head Diameter ◽  
Head Weight ◽  
Average Plant ◽  
Early Flower ◽  
Average Plant Height

This experiment was conducted during September, 2011 to March, 2012 in the experimental field of Department of Horticulture, Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Gazipur to find out the effect of planting date on the yield of broccoli genotypes. There were five genotypes viz. Early green, Forest green, Green calabrese, Premium crop and Green king and four planting dates viz. 2 October, 27 October, 21 November and 16 December. The treatment effects were statistically analyzed and found significant in most of the characters studied. Genotype Green calabrese was the highest in average plant height (53.70 cm). Green king produced the maximum spread diameter (69.23 cm), stem diameter (30.35 mm) and early initiation of floral head. Genotype Early green performed the best regarding head weight (343.87 g), yield per plant (477.4 g) and yield (19.10 t/ha). Broccoli planted on 21 November initiated early flower head, maximum head diameter (16.99 cm), head weight (314.49 g), yield per plant (453.64 g) and total yield (18.15 t/ha). The genotype Early green planted on 21 November showed the best performance in yield per plant (580.17 g) and yield hectare (23.21 t/ha).Bangladesh J. Agril. Res. 40(3): 465-478, September 2015

scholarly journals Using Canopy Measurements to Predict Soybean Seed Yield

2021 ◽  
Vol 13 (16) ◽  
pp. 3260
Author(s):  
Peder K. Schmitz ◽  
Hans J. Kandel
Keyword(s):  
Seed Yield ◽  
Prediction Models ◽  
Plant Density ◽  
Soybean Seed ◽  
Canopy Cover ◽  
Growing Season ◽  
Practical Method ◽  
Coefficient Of Determination ◽  
Planting Dates ◽  
The Individual

Predicting soybean [Glycine max (L.) Merr.] seed yield is of interest for crop producers to make important agronomic and economic decisions. Evaluating the soybean canopy across a range of common agronomic practices, using canopy measurements, provides a large inference for soybean producers. The individual and synergistic relationships between fractional green canopy cover (FGCC), photosynthetically active radiation (PAR) interception, and a normalized difference vegetative index (NDVI) measurements taken throughout the growing season to predict soybean seed yield in North Dakota, USA, were investigated in 12 environments. Canopy measurements were evaluated across early and late planting dates, 407,000 and 457,000 seeds ha−1 seeding rates, 0.5 and 0.8 relative maturities, and 30.5 and 61 cm row spacings. The single best yield predictor was an NDVI measurement at R5 (beginning of seed development) with a coefficient of determination of 0.65 followed by an FGCC measurement at R5 (R2 = 0.52). Stepwise and Lasso multiple regression methods were used to select the best prediction models using the canopy measurements explaining 69% and 67% of the variation in yield, respectively. Including plant density, which can be easily measured by a producer, with an individual canopy measurement did not improve the explanation in yield. Using FGCC to estimate yield across the growing season explained a range of 49% to 56% of yield variation, and a single FGCC measurement at R5 (R2 = 0.52) being the most efficient and practical method for a soybean producer to estimate yield.

Response of soya beans to planting date in south-eastern Queensland. II.* Vegetative and reproductive development

1974 ◽  
Vol 25 (5) ◽  
pp. 723 ◽  
Author(s):  
RJ Lawn ◽  
DE Byth
Keyword(s):  
Seed Yield ◽  
Vegetative Growth ◽  
Growth Period ◽  
Reproductive Development ◽  
Planting Date ◽  
Biological Efficiency ◽  
Vegetative Development ◽  
Planting Dates ◽  
Growing Period ◽  
Seed Yields

Vegetative and reproductive development of a range of soya bean cultivars was studied over a series of planting dates in both hill plots and row culture at Redland Bay, Qld. Responses in the extent of vegetative and reproductive development were related to changes in the phasic developmental patterns. The duration and extent of vegetative development for the various cultivar-planting date combinations were closely associated with the length of the period from planting to the cessation of flowering. Thus, vegetative growth was greatest for those planting dates which resulted in a delay in flowering and/or extended the flowering phase. Similarly, genetic lateness of maturity among cultivars was associated with more extensive vegetative development. Seed yield per unit area increased within each cultivar as the length of the growing period was extended until sufficient vegetative growth occurred to allow the formation of closed canopies under the particular agronomic conditions imposed. Further increases in the length of the period of vegetative growth failed to increase seed yield, and in some cases seed yields were actually reduced. Biological efficiency of seed production (BE) was negatively correlated with the length of the vegetative growth period. Differences in BE among cultivar-planting date combinations were large. It is suggested that maximization of seed yield will necessitate an optimum compromise between the degree of vegetative development and BE. Optimum plant arrangement will therefore vary, depending on the particular cultivar-planting date combination. ___________________ \*Part I, Aust. J. Agric. Res., 24: 67 (1973).

RESPONSES TO PLANTING DATE AND POPULATION DENSITY BY EARLY-MATURING SORGHUM HYBRIDS IN ONTARIO

1981 ◽  
Vol 61 (2) ◽  
pp. 265-273
Author(s):  
D. J. HUME ◽  
YILMA KEBEDE
Keyword(s):  
Plant Density ◽  
Late Summer ◽  
Hybrid Plant ◽  
Planting Date ◽  
Planting Dates ◽  
Grain Yields ◽  
South Central ◽  
Early Maturing ◽  
Plant Densities ◽  
Sorghum Grain

Early-maturing grain sorghum (Sorghum bicolor (L.) Moench) hybrids which have potential usefulness in southern Ontario are commercially available. One such hybrid, Pride P130, and two experimental hybrids, Pride X4043 and Pride X3160, were grown at three planting dates and three plant densities in 1975 and 1976 at Elora, Ontario. There were several hybrid × planting date and hybrid × plant density interactions for the development and yield parameters measured. However, grain yields of all hybrids decreased by about 10% per week when plantings were delayed 2 or 4 wk after mid-May in 1975. In 1976, yields declined even more after late planting. Increasing populations from 75 000 to 300 000 plants/ha in 1975 increased grain yields from 4.3 to 6.0 t/ha, averaged over hybrids and planting dates. In 1976, raising populations from 150 000 to 450 000 plants/ha increased average yields from 3.2 to 3.7 t/ha. P130 was the earliest and best-yielding hybrid in both years. In 1975, which had a warm May and near-average temperatures, the best treatment yielded 7.3 t grain/ha and hybrids at all planting dates matured. The best treatment approached grain corn (Zea mays L.) yields. In 1976 with a cool spring and late summer, the highest grain yield was 5.7 t/ha with early planting, but 11 June plantings did not mature. In south-central Ontario, sorghum grain yields appear less reliable than those of corn.

EFFECTS OF PLANT DENSITY AND PLANTING DATE ON LEAF NUMBER AND SOME DEVELOPMENTAL EVENTS IN CORN

1976 ◽  
Vol 56 (3) ◽  
pp. 691-698 ◽  
Author(s):  
E. E. N. A. BONAPARTE ◽  
R. I. BRAWN
Keyword(s):  
Plant Density ◽  
Planting Date ◽  
Leaf Number ◽  
Planting Dates ◽  
Corn Hybrids ◽  
Grain Moisture ◽  
Linear Correlations

The effects of plant density on leaf number and some developmental events in four corn hybrids were studied in 1969 and 1970. Increase in plant density was accompanied by a decrease in leaf number, an increase in the periods from planting to tassel emergence and mid-silk, and an increase in grain moisture at harvest. High linear correlations between leaf number and these developmental events were obtained within the spacing environments. The effects of eight planting dates on leaf number and some developmental events were studied in 1970. Delayed planting was accompanied by changes in leaf number, with a significant increase in leaf number at the middle planting dates, a decrease in the periods from planting to tassel emergence and mid-silk, and an increase in grain moisture at harvest. Leaf number was highly significantly correlated with these developmental events within the planting date environments.

Planting date and suboptimal seedbed temperature effects on dry bean establishment, phenology and yield

2004 ◽  
Vol 84 (1) ◽  
pp. 31-36 ◽  
Author(s):  
P. Balasubramanian ◽  
A. Vandenberg ◽  
P. Hucl
Keyword(s):  
Seed Yield ◽  
Planting Date ◽  
Planting Dates ◽  
Dry Bean ◽  
Yield And Quality ◽  
Seeding Date ◽  
Early Fall ◽  
Plant Stand ◽  
The Difference ◽  
Low Temperature Emergence

Seedbed temperatures below 15°C are detrimental to dry bean germination and emergence. This field study was conducted to determine the effects of suboptimal seedbed temperatures on dry bean emergence, and the cumulative effects of suboptimal seedbed temperatures during emergence on crop phenology and yield. Selected dry bean cultivars were planted in mid- and late May when seedbed temperatures were below and above the suboptimal temperature (15°C), respectively, at Saskatoon, SK. Emergence, cumulative thermal units to anthesis and maturity, seed yield, yield components and percent frost-damaged seeds were evaluated in 1999 and 2000. The final seedling count at 30 d after planting was 81% for the mid-May planting and 94% for the late May planting. However, the difference in plant stand was not statistically significant. Year-to-year differences in weather influenced the response of dry bean to planting date for maturity and seed yield. The mid-May planting produced the highest seed yield in 1999, when the two indeterminate cultivars in the late May planting failed to mature prior to the mid September frost. The mid-September frost also resulted in a high percent frost-damaged seeds for the late May planting. In 2000, when the first fall frost was in late September, maturity and seed yield of dry bean cultivars were equivalent for planting dates. The mid-May planted dry bean cultivars will result in higher seed yield and quality compared to the conventional late May planting in years with an early fall frost. Key words: Dry bean, seeding date, low temperature, emergence, maturity

scholarly journals EFFECT OF PLANTING DATE, PINCHING, AND PLANT DENSITY ON QUALITY AND YIELD OF FIELD-GROWN GODETIA

HortScience ◽  
1992 ◽  
Vol 27 (6) ◽  
pp. 649d-649
Author(s):  
Robert G. Anderson ◽  
Robert L. Geneve
Keyword(s):  
Plant Density ◽  
Planting Date ◽  
Separate Experiment ◽  
Plastic Mulch ◽  
Planting Dates ◽  
Plant Densities ◽  
Production Practices ◽  
Black Plastic

Different planting dates, plant densities and pinching practices were used to determine the production practices that produced the best quality cut stems from field grown godetia under Kentucky conditions. Godetia `Grace Salmon' transplants were planted at a plant density of 40 plants m-2 on Mar 23, Apr 8 and Apr 23, 1991 in ground beds with black plastic mulch. All plants flowered in early to mid June, but plants from the Mar 23 planting date had the highest yields of commercial quality stems (387 stems m-2) and over 80% of the stems were longer than 55 cm. In a separate experiment, transplants of `Grace Red' and `Grace Rose Pink' were planted on April 5 at plant densities of 4.5 m-2 (unpinched), 10 m-2 (soft pinch on May 1) and 23 m-2 (hard pinch on May 1). Pinching treatments were used to increase the number of secondary and tertiary branches on each plant. Although the pinching treatments produced more branches, a low percentage of the branches were commercial quality cut stems.

scholarly journals Heterotic Effects in Fls and Inbreeding Depression in F2 Hybrids of Sunflower

2015 ◽  
Vol 58 (1) ◽  
pp. 1-10
Author(s):  
Shahnaz Memon ◽  
Muhammad Jurial Baloch ◽  
Gul Muhammad Baloch ◽  
Muhammad Ibrahim Keerio
Keyword(s):  
Plant Height ◽  
Inbreeding Depression ◽  
Seed Yield ◽  
Block Design ◽  
Oil Yield ◽  
F1 Hybrids ◽  
Hybrid Vigour ◽  
Head Diameter ◽  
Days To Maturity ◽  
F2 Hybrids

Genetically diverse female lines of sunflower were crossed with male testers to get heterotic hybrids. Studies were carried-out during 2008-2010 at Experiment filed of Agriculture Research Institute, Tandojam, Sindh, Pakistan. Six female lines like T-4-0319, PAC-0505, HO-I, Hysun-33, Peshawar-93 and CMS-03 and three testers i.e., PAC-0306, PAC-64-A and SF-187 were crossed in a line ´ tester mating design, thus 18 F1 and F2 hybrids were developed for evaluation of heterosis and inbreeding depression for days to initial flowering, days to maturity, leaves/plant, plant height (cm), head diameter (cm), 1000-achene weight (g), seed yield kg/ha and oil yield kg/ha. The experiment was conducted in a randomised complete block design with four replications. The analysis of variance revealed significant differences among parents, F1s and F2 hybrids for all the traits studied. The existence of significant genetic variability among the plant traits is particularly useful because variations in these traits would allow further improvement in sunflowerseed yield and oil traits. The F1 hybrids HO-I ´ PAC-0306 and HO-I PA ´ C-64-A exhibited desirable negative mid and better parent heterosis for days to initial flowering, days to maturity and plant height. These hybrids also manifested desirable positive heterotic effects for leaves/plant, head diameter, 1000-achene’s weight, seed yield and oil yield. Inbreeding depression for phenological, seed yield and oil traits  showed that desirable high inbreeding depression was observed in hybrids HO-I ´ P´AC-64-A, HO-I ´ PAC-0306 and HO-I ´ SF-187 for days to initial flowering, similarly T-4-0319 ´ PAC-0306, PAC-0505 ´ SF-187 and HO-I ´ PAC-64-A explicated maximum but rewarding inbreeding depression for days to maturity. The F2 hybrids Hysun-33 ´ SF-187 and Peshawer-93 ´ PAC-64-A may be the most desirable ones in the sense that they recorded comparatively moderate inbreeding depression with enough number of leaves to be productive if F2 hybrids are to be exploited for hybrid vigour. Low inbreeding depression for various traitsindicated that such hybrids some how favour the usefulness of F2 hybrids in sunflower. 

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