Earliness of an indeterminate crop, Vigna unguiculata (L.) Walp., as affected by drought, temperature, and plant density

1982 ◽  
Vol 33 (3) ◽  
pp. 531 ◽  
Author(s):  
DA Grantz ◽  
AE Hall

Earliness of an indeterminate crop, Vigna unguiculata (L.) Walp., was studied to aid development of selection techniques for improving adaptation to semiarid environments. Earliness was based upon the time of first appearance of floral buds and flowers, proportion of shoot dry matter in reproductive parts at midseason, and time of maturity. A cowpea land race, Chino 3, was earlier than cultivars California Blackeye No. 3 and No. 5, with respect to all of these criteria. Time to flowering from different sowing dates was related to heat units, which were calculated from daily mean air temperature above a base temperature of c. 10�C. The proportions of shoot dry matter in reproductive parts during early stages of pod-filling were greater with moderate drought but were unaffected by severe drought, compared with the response of adequately irrigated plants. Widely spaced plants exhibited greater proportions of shoot dry matter in reproductive parts at midseason than did closely spaced plants. Adaptation of cowpeas to semiarid environments may be improved by selecting for early partitioning of carbohydrates to reproductive parts. Selection for early partitioning may be more effective in adequately watered conditions, owing to extreme variability under drought, and at wide and precise spacing.

Author(s):  
A.V. Cherkashyna ◽  
◽  
E.F. Sotchenko ◽  

Dry matter yield is an objective indicator of assessing the productivity of corn hybrids grown for silage and green fodder. The aim of the work was to identify optimal planting dates to obtain maximum yield of dry matter at the late milk stage of development for hybrids of corn depending on groups of maturity under rain-fed conditions of the Crimean steppe zone. The sowing dates of the field experiment were on April 5th, 15th, and 25th. We studied hybrids of corn of different groups of maturity. Soil – chernozems southern low-humus. Meteorological conditions in 2016 were characterized by increased moisture availability (Selyaninov Hydrothermal Coefficient (HTC) 1.46). In 2017, severe drought was noted (HTC 0.34). Moisture availability was insufficient in 2018 and 2019 (HTC 0.79 and 0.78, respectively). In 2016-2019, the best planting date for hybrid ‘Nur’ was April 15th; the dry matter yield in the late milk stage was 6.69 t/ha. For the medium- early hybrid ‘Mashuk 220 MV’, the best sowing dates were April 15th and 25th; dry matter yield was 5.95 and 5.78 t/ha, respectively. Hybrid ‘Mashuk 355 MV’ demonstrated higher dry matter yield on April 5th and 15th (7.12 and 6.99 t/ha). However, the planting date of April 25th led to significant yield decreased (to 6.1 t/ha).


1986 ◽  
Vol 37 (5) ◽  
pp. 513 ◽  
Author(s):  
R Ferraris ◽  
DA Charles-Edwards

Well-watered crops of sweet sorghum (cv. Wray) and forage sorghum (cv. Silk) were grown in south-eastern Queensland. Treatments consisted of four sowing dates, two intra-row spacings and harvests taken at six physiological growth stages from the third ligule to 3 weeks after grain maturity. Plant density effects on the concentration of sugars and nitrogen were slight, and changes in yields of these components were a function of density effects on dry matter yields. At any growth stage, the concentration of sugars in both cultivars was decreased with delay in sowing date. The delay in sowing date led to an increased nitrogen concentration in cv. Wray, but in cv. Silk the nitrogen concentration was highest in early and late sowings. At maturity, the concentration of sugars in cv. Wray averaged 40'70, 10 times the level in cv. Silk. In both cultivars, accumulation was a near linear function of either time or radiation sum. The partitioning of carbohydrate differed little between cultivars but altered with their ontogeny. The efficiency of light use for sugars production was greater in cv. Wray and altered with ontogeny. In contrast, concentration of nitrogen was similar for both cultivars and decreased curvilinearly with time or degree days. The partitioning of nitrogen altered with ontogeny and the amount partitioned to leaf material was greater in cv. Silk pre-anthesis but was less post-anthesis. Yield of stem sugars in cv. Wray exceeded 10 t ha-1 when the crops were sown early in the season, but was only 3 t ha-1 with late-sown crops.


Irriga ◽  
2015 ◽  
Vol 20 (3) ◽  
pp. 502-513 ◽  
Author(s):  
Simone Raquel Mendes de Oliveira ◽  
Aderson Soares de Andrade Júnior ◽  
Valdenir Queiroz Ribeiro ◽  
Ramilos Rodrigues de Brito ◽  
Marcus Willame Carvalho

INTERAÇÃO DE NÍVEIS DE ÁGUA E DENSIDADE DE PLANTAS NO CRESCIMENTO E PRODUTIVIDADE DO FEIJÃO-CAUPI, EM TERESINA, PI  SIMONE RAQUEL MENDES DE OLIVEIRA1; ADERSON SOARES DE ANDRADE JÚNIOR2; VALDENIR QUEIROZ RIBEIRO3; RAMILOS RODRIGUES DE BRITO4 E MARCUS WILLAME CARVALHO5 1Eng. Agrônoma, Doutora em Engenharia Agrícola, Professora Colégio Técnico de Teresina, Teresina – PI, e-mail: [email protected]. Agrônomo, Doutor em Irrigação e Drenagem, Pesquisador da Embrapa Meio-Norte, Teresina – PI.3Eng. Agrônomo, Mestre em Estatística Experimental, Pesquisador da Embrapa Meio-Norte, Teresina – PI.4Eng. Agrônomo, Doutorando em Irrigação e Drenagem, UNESP/FCA, Botucatu – SP.5Eng. Agrônomo, Mestre em Irrigação e Drenagem, CCA-UFPI, Teresina – PI.  1 RESUMO O objetivo desse trabalho foi avaliar a influência de níveis de água e densidade de plantas no crescimento (matéria seca e área foliar) e produtividade do feijão-caupi (Vigna unguiculata L. Walp.). O experimento foi conduzido na área experimental da Embrapa Meio-Norte, localizada no município de Teresina, Piauí - Brasil, no período de julho a setembro de 2012. O solo local foi classificado como Argissolo Vermelho-Amarelo de textura franco-arenosa. Utilizou-se o delineamento experimental em blocos casualizados, com quatro repetições. Os tratamentos foram arranjados num esquema fatorial 5 x 4, sendo os fatores cinco níveis de irrigação: 393,53; 340,34; 300,50; 260,39 e 201,73 mm, aplicados por meio de um sistema de irrigação por aspersão convencional, e quatro densidades de plantas: 150.000; 200.000; 250.000; 300.000 plantas ha-1. Apenas na matéria seca não houve interação significativa entre os níveis de irrigação e densidade de plantas. A área foliar, produtividade de grãos, número de vagens por planta, massa de vagens, produtividade de vagens, comprimento de vagem e massa de cem grãos que apresentaram valores máximos de: 1.301,89 cm²; 1.668,86 kg ha-1; 2,24; 2.248,16 kg; 1.873,45 kg ha-1; 18,70 cm e 22,72 g, alcançados com as lâminas de: 367,86; 390,88; 393,53; 393,53; 393,53; 348,40 e 322,63 mm associados às densidades de: 188.000; 241.000; 110.000; 254.000; 254.000; 223.000 e 300.000 plantas.ha-1, respectivamente. Palavras-chave: estresse hídrico, adensamento, competição intraespecífica.  OLIVEIRA, S. R. M. de; ANDRADE JÚNIOR, A. S. de; RIBEIRO, V. Q.; BRITO, R. R. de; CARVALHO, M. W. INTERACTION BETWEEN LEVELS OF WATER AND PLANT DENSITY ON GROWTH AND YIELD OF COWPEA IN TERESINA, PI   2 ABSTRACT The objective of this study was to evaluate the effect of levels of water, plant density and their interaction  on growth (dry matter and leaf area) and yield of cowpea (Vigna unguiculata L. Walp.). The experiment was carried out at the experimental area of Middle- North Embrapa in Teresina city, Piauí-Brazil from July to September 2012 in a Ultisol soil.  A randomized block experimental design was used with four replicates.  Treatments were applied in a   5 x 4 factorial design and 5 levels of irrigation as factors:  393.53; 340.34; 300.50; 260.39 and 201.73 mm applied through  an irrigation system by conventional sprinkler, and four plant densities:  150,000; 200,000; 250,000; 300,000 plants ha-1. A significant interaction between irrigation levels and plant density was found in all study parameters except for dry matter.  Leaf area, grain yield, number of pods per plant, pod weight, pod yield, pod length and hundred grain weight had maximum values of   1,301.89 cm²;  1,668.86 kg ha-1; 2.24; 2,248.16 kg; 1,873.45 kg ha-1; 18.70 cm and 22.72 g,  which were reached using the following  water depths:   367.86; 390.88; 393.53; 393.53; 393.53; 348.40 and  322.63 mm associated with densities of : 188,000; 241,000; 110,000;254,000; 254,000; 223,000 and  300,000 plants.ha-1 , respectively. Keywords: water stress, density, intraspecific competition. 


1993 ◽  
Vol 29 (4) ◽  
pp. 491-501 ◽  
Author(s):  
M. J. Bell ◽  
G. C. Wright ◽  
G. Harch

SummaryThe partitioning of dry matter between vegetative and reproductive yield components was analysed for four diverse peanut cultivars at a range of sowing dates and plant populations in sub-tropical Queensland, Australia. Rates of accumulation of pods (pod addition) varied significantly with both cultivar and sowing date. Within cultivars, much of this variation could be attributed to variation in crop growth rate during the critical pod addition period. The proportion of current assimilate distributed to pods depended on inherent cultivar characteristics and also correlated well with the current crop growth rate relative to the crop growth rate during pod addition (that is, with relative source activity). Neither plant density nor spatial arrangement had any significant effects on patterns of assimilate distribution. All cultivars appeared capable of remobilizing stored assimilate to maintain constant rates of pod yield increase despite fluctuations in crop growth rate which might be expected to produce short term source limitations to pod yield accumulation. The harvest index (HI) increased linearly during the entire pod fill period in all cultivars except the very early maturing Spanish cultivar Chico. Neither density nor spatial arrangement affected rate of increase in HI except in Chico, where increased density produced increased rates of increase in HI. Variation in the rate of HI increase among sowing dates was small.Distributión de la materia seca en el maní


1978 ◽  
Vol 14 (3) ◽  
pp. 197-203 ◽  
Author(s):  
J. O. Akinola ◽  
J. H. Davies

SUMMARYFourteen varieties of cowpea (Vigna unguiculata (L.) Walp.) were compared for yields of forage and seed from two sowing dates, using various agronomic parameters. Yields ranged from 1048 to 5044, 185 to 920 and 864 to 3321 kg/ha for dry matter, crude protein and seed respectively, with advantages from spreading as against semi-erect types, and early rather than late July sowing. IVu 1283-1 and IVu 1283-2 effectively combined vegetative and seed yield, and appeared most suitable for fodder and seed production. A simple forage yield index (FYI), useful in yield prediction, was evolved.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 523c-523
Author(s):  
Siegfried Zerche

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.


Author(s):  
L. S. Sampaio ◽  
R. Battisti ◽  
M. A. Lana ◽  
K. J. Boote

Abstract Crop models can be used to explain yield variations associated with management practices, environment and genotype. This study aimed to assess the effect of plant densities using CSM-CROPGRO-Soybean for low latitudes. The crop model was calibrated and evaluated using data from field experiments, including plant densities (10, 20, 30 and 40 plants per m2), maturity groups (MG 7.7 and 8.8) and sowing dates (calibration: 06 Jan., 19 Jan., 16 Feb. 2018; and evaluation: 19 Jan. 2019). The model simulated phenology with a bias lower than 2 days for calibration and 7 days for evaluation. Relative root mean square error for the maximum leaf area index varied from 12.2 to 31.3%; while that for grain yield varied between 3 and 32%. The calibrated model was used to simulate different management scenarios across six sites located in the low latitude, considering 33 growing seasons. Simulations showed a higher yield for 40 pl per m2, as expected, but with greater yield gain increments occurring at low plant density going from 10 to 20 pl per m2. In Santarém, Brazil, MG 8.8 sown on 21 Feb. had a median yield of 2658, 3197, 3442 and 3583 kg/ha, respectively, for 10, 20, 30 and 40 pl per m2, resulting in a relative increase of 20, 8 and 4% for each additional 10 pl per m2. Overall, the crop model had adequate performance, indicating a minimum recommended plant density of 20 pl per m2, while sowing dates and maturity groups showed different yield level and pattern across sites in function of the local climate.


Author(s):  
J.D. Leaver ◽  
R.C. Campling

Supplementary feeding of grazing dairy cows is often uneconomic, and whilst supplementation with silage (buffer feeding) can be worthwhile, this often leads to a depletion of winter forage stores. In this study, a mixture of brewers grains and treated straw was used as a supplement. Offered as a 1:1 mixture in the dry matter (DM), it is a purchased substitute for grass silage, having a similar cost, and similar metabolisable energy (ME) and crude protein (CP) contents. The high seasonality adjustments to milk price in mid-late season make supplementation potentially worthwhile.Experiments were carried out from April to September in 1988 and 1989, which had moderate and very low rainfall respectively. Each year 20 British Friesian cows which calved December to March (1988 experiment) and February-April (1989) were allocated at random to either treatment B or C. In B, the cows were offered a 1:1 mixture (DM basis) of brewers grains and NaOH treated chopped barley straw for 60 minutes after morning milking. In C, the cows received no supplement. Both groups were fed 1.0 kg/day of concentrates in the milking parlour. Due to the severe drought in 1989, concentrate feeding was increased to 5.0 kg/day for all cows during the last 4 weeks of the experiment. Also, urea-treated whole crop wheat was fed at a level of 2.5 kg DM/day during the last 7 days.


1951 ◽  
Vol 41 (3) ◽  
pp. 271-281 ◽  
Author(s):  
E. S. Bunting ◽  
G. E. Blackman

Between 1942 and 1950, some thirty field experiments have been carried out in the southern half of England to assess the potential value, either for grain or forage production, of seventeen openpollinated flint or dent maizes together with twentynine single or double hybrids of American or Canadian origin.Early-maturing flint varieties will consistently ripen grain, but before mechanical threshing or storage, the cobs require drying. Sibthorp, a mass selection made from an unknown German variety, is the earliest and most productive flint maize so far tested, and in the experiments has yielded as much as 39 cwt. of grain per acre with an average of 24 cwt. The earliest American hybrids, i.e. those with a U.S.A. rating of 80 days from sowing to maturity, give very high yields of grain in favourable seasons. Within the group Wisconsin 240–275, a yield level equal to or exceeding 50 cwt./acre has on occasion been recorded. On the other hand, in the most unfavourable years, such hybrids just failed to produce ripe cobs.Attempts to maintain sixty-five parent inlines of the earliest hybrids have largely failed. However, many of the parent single crosses have matured, and the production on a field scale of the double-cross seed of both Wisconsin 240 and 255 has been carried out.Spacing experiments indicate that for optimum grain production a density of 6 plants/sq.yd. is required for both flint varieties and the earliest hybrids. A spatial arrangement of individual plants is to be preferred to that of groups or hills.American hybrids, in the class of ‘90 days’ to maturity, will in all but the most unfavourable seasons reach the ‘early-dent’ stage of the grain before the incidence of autumn frosts. Yields of dry matter of plants harvested in this phase have ranged from 30 to 85 cwt. of dry matter per acre. In these trials, the plant density was standardized at 4 plants/sq.yd. and higher densities may be demanded for optimal yields.The ratio of the ‘ear’ (that is, the cob, immature grain and enclosing leaf sheaths) to the total shoot weight at harvest varies greatly with the variety or hybrid. With White Horsetooth, the usual variety grown for fodder in England, no cobs are formed before the plants are killed by frost, while with the early hybrids, the ear may be half the weight of the whole shoot.The earliest variety Sibthorp from an early May sowing takes approximately 70–80 days to reach full anthesis, while ‘80-day’ American hybrids are a week later. From sowing to full maturity the period in England is from 140 to 160 days, thus compared to conditions in Minnesota the period is nearly twice as long. Because of the much slower rate of development and because of the humidity of English autumns, it is concluded that until the date of maturity can be advanced some 14 days, grain production on a field scale is not yet feasible. On the other hand, many of the American hybrids are well fitted to the production of silage. The greatest drawback to the introduction of such hybrids is the liability of the seed and seedlings to be attacked by rooks.


2017 ◽  
Vol 14 (2) ◽  
pp. 155-160
Author(s):  
MAR Sharif ◽  
MZ Haque ◽  
MHK Howlader ◽  
MJ Hossain

The experiment was conducted at the field laboratory of the Patuakhali Science and Technology University, Patuakhali, Bangladesh during the period from November, 2011 to March 2012 under the tidal Floodplain region to find out optimum sowing time for the selected three cultivars (BARI Sharisha-15, BINA Sharisha-5 and BARI Sharisha-9). There were four sowing dates viz. 30 November, 15 December, 30 December and 15 January. Significant variations due to different sowing dates were observed in plant height, total dry matter, leaf area index, number of siliqua plant-1, seeds silique-1, 1000-grain weight, grain yield and HI. Results showed that the highest grain yield (1.73 t ha-1) was obtained from the first sowing (30 November) with BINA Sharisha-5 and it was significantly different from the yields of all other combination.J. Bangladesh Agril. Univ. 14(2): 155-160, December 2016


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