Agronomic studies on soybean (Glycine max (L.) Merrill) in the dry season of the tropics. II. Interaction of sowing date and sowing density

1991 ◽  
Vol 42 (7) ◽  
pp. 1093 ◽  
Author(s):  
JD Mayers ◽  
RJ Lawn ◽  
DE Byth
Keyword(s):  
Biomass Production ◽  
Seed Yield ◽  
Management Practices ◽  
Interaction Analysis ◽  
Sowing Date ◽  
Dry Season ◽  
High Yield ◽  
Total Biomass ◽  
Wet Season ◽  
Precocious Flowering

An analysis was undertaken of the development, growth and seed yield of irrigated soybean crops grown during the dry season in the semi-arid tropics of north-western Australia, to establish whether constraints to seed yield induced by precocious flowering could be overcome agronomically by manipulating sowing date and/or sowing density. Three agronomically improved cultivars and a later-flowering landrace cultivar were tested using irrigation, fertility and pest management practices designed to minimize constraints to yield. Maximum seed yields were 3.5-4.0 t ha-1, with large genotype x sowing date x sowing density interaction. Analysis of vegetative growth showed that higher sowing densities stimulated more rapid leaf area development and earlier canopy closure, and enhanced total biomass production. However, very high sowing densities were needed to maximize yields of most genotypes, while lodging precluded high yield being realized from the greater biomass production of high density sowings of the landrace genotype. Delaying sowing from April to June delayed flowering, increased biomass production and marginally enhanced yields, but not sufficiently to offset potential problems caused by maturation into hot dry conditions prior to the wet season. It was concluded that agronomic strategies alone were insufficient to overcome the constraints to yield of present soybean genotypes in the dry season.

Agronomic studies on soybean (Glycine max (L.) Merrill) in the dry seasons of the tropics. I. Limits to yield imposed by phenology

1991 ◽  
Vol 42 (7) ◽  
pp. 1075 ◽  
Author(s):  
JD Mayers ◽  
RJ Lawn ◽  
DE Byth
Keyword(s):  
Leaf Area ◽  
Biomass Production ◽  
Seed Yield ◽  
Management Practices ◽  
Dry Season ◽  
Canopy Development ◽  
Precocious Flowering ◽  
The Tropics ◽  
Area Development ◽  
Leaf Area Development

An analysis was undertaken of the development, growth and seed yield of irrigated soybean crops grown during the dry season of the semi-arid tropics in north-western Australia, to establish yield potentials and identify major climatic or physiological constraints. Ten tropically adapted genotypes were grown at three sowing times, using agronomic management practices designed to maximize productivity and minimize constraints due to water supply, fertility, weeds and insects. In addition to phenology, seed yield, dry matter (DM) accumulation, and seed and plant morphological traits, measurements were made at the beginning and end of flowering of DM accumulation, leaf area development and interception of photosynthetically active radiation (PAR). Harvest indices were generally large, but maximum seed yields were only c. 3 t ha-1, apparently because of inadequate biomass production. The analysis of growth and development suggested that DM accumulation during the vegetative phase was limited primarily by cumulative PAR interception by the crop canopy rather than the efficiency of conversion of intercepted PAR. In turn, both cumulative PAR interception, and canopy leaf area development, were constrained by precocious flowering, induced by the comparatively short-day/warm temperature conditions of the dry season. It was concluded that yield improvement strategies for the dry season will need to be based on agronomic and/or breeding strategies to enhance canopy development and improve biomass production.

Agronomic studies on soybean (Glycine max (L.) Merrill) in the dry season of the tropics. III. Effect of artificial photoperiod extension on phenology, growth and seed yield

1991 ◽  
Vol 42 (7) ◽  
pp. 1109 ◽  
Author(s):  
JD Mayers ◽  
RJ Lawn ◽  
DE Byth
Keyword(s):  
Seed Yield ◽  
Dry Season ◽  
Yield Potential ◽  
Wet Season ◽  
Canopy Development ◽  
North West ◽  
Precocious Flowering ◽  
Natural Photoperiod ◽  
Artificial Photoperiod ◽  
Delayed Flowering

Soybean cultivars developed for the tropical wet season performed poorly when grown in the dry season in north-west Australia. The proposition that breeding for later flowering time might enhance yields was tested by using artificial photoperiod extension (14 h day-1 for 28 days post-emergence) to delay flowering of field plots of agronomically improved genotypes. Canopy development and interception of photosynthetically active radiation (PAR), dry matter (DM) accumulation, seed yield and seed composition were examined, and compared with that from plants grown under natural photoperiods. Photoperiod extension delayed flowering an average 24 days, and maturity by an average 14.5 days, the effect being greater in the earlier-flowering genotypes. Differences among genotypes and photoperiod treatments in above-ground DM at the beginning and end of flowering were almost entirely due to the consequences of differences in phenology for cumulative PAR interception. DM at maturity was a simple linear function of crop duration (r2 = 0.95**), while seed yield exhibited an optimum-type response with DM ( R2 = 0.79**). The net consequence was that photoperiod extension increased DM production by an average 2.23 t ha-1 and seed yield by an average 0.65 t ha-1. The analyses suggested that a crop duration of c. 143-146 days would be needed to maximize seed yield under the agronomic conditions of the study, whereas the longest duration among the agronomically improved genotypes under natural photoperiod conditions was 136 days. It was concluded that breeding to constrain precocious flowering under short day conditions would be a viable strategy to improve the yield potential of soybean in the dry season.

scholarly journals THE EFFECT OF SEASONAL VARIATION ON PERFORMANCE OF EGG TYPE POULTRY: A Case Study of Mitchell Farms, Mosogar, Delta State, Nigeria

2021 ◽  
Vol 24 (2) ◽  
pp. 101-105
Author(s):  
E. E. Guobadia
Keyword(s):  
Seasonal Variation ◽  
Feed Intake ◽  
Egg Production ◽  
Management Practices ◽  
Secondary Data ◽  
Dry Season ◽  
Wet Season ◽  
Egg Hatchability ◽  
Significant Difference

The study was designed to find out the effect of seasonal variation on poultry in Delta State of Nigeria. The variables considered were mortality rate, feed intake, egg production and egg hatchability in the wet and dry seasons of the year. Secondary data were also collected from records kept in the farm. Sites 4AHI-BLK,5AKI-BLK, 9H/BF and 10H/BF were used for the study with each having an average of 2,500-3,500 birds of the same breed and sex aged 1-9 weeks and 21-52weeks. The records were grouped into dry season (October-March) and wet season (April-September) covering three years, 1991-1994. The analysis of the result showed that seasonal variation does not have any significant effect (P < 0.05) on mortality and feed intake in the two seasons. However percentage egg production and egg hatchability revealed a significant difference (P < 0.05) between the two seasons, with a mean % egg production and hatchability of 74±.03 and 80.6 in the wet season and 53.67±0.01 and 55.9 respectively in the dry season. Recommendation is therefore made for proper planning which ensures the utilization of wet and dry season management practices to reduce the effect of high humidity and embient temperature on production.

scholarly journals Genotype X Environment Interaction Analysis of Faba Bean (Vicia faba L.) for Biomass and Seed Yield across Different Environments

2021 ◽  
Vol 13 (5) ◽  
pp. 2586
Author(s):  
Panayiota Papastylianou ◽  
Dimitrios N. Vlachostergios ◽  
Christos Dordas ◽  
Evangelia Tigka ◽  
Paschalis Papakaloudis ◽  
...  
Keyword(s):  
Vicia Faba ◽  
Seed Yield ◽  
Faba Bean ◽  
Interaction Analysis ◽  
Grain Legumes ◽  
High Yield ◽  
Environment Interaction ◽  
Crop Species ◽  
South Central ◽  
Vicia Faba L

Development of high yielding and stable cultivars of various legume crops across different environments is very important for their adoption by farmers. In addition, climate change sets new challenges to major crop species and especially to grain legumes such as faba bean (Vicia faba L.) for adaptation to stressful environments. The present study focused on evaluating faba bean genotypes developed for yield and stability across different environments. The study was conducted in three areas of Greece (South, Central, and North) for two consecutive growing seasons (2018–2019 and 2019–2020). Biomass yield, seed yield, and yield components were studied together with plant height, earliness, and water use efficiency. Genotype, environment, and their interaction affected most of the studied characteristics. The environment was the major source of variation for most of the characteristics, as it explained 81–93% of total variation, and only in the thousand seed weight the variation was 49% for the environment and 40% for the genotype. Genotype had a much smaller effect on the remaining characteristics (1.2–3.9%), and the interaction between environment x genotype accounted for up to 0.5–17% of the variation. GGE-biplot analysis for high yield and stability across different environments revealed three genotypic types: genotypes well adapted either for biomass or seed yield and genotypes with high adaptation capacity for both traits under typical Mediterranean conditions. These results indicated that screening faba bean genotypes under different environmental field conditions is essential to identify adaptable cultivars to be cultivated for biomass and/or seed yield or to be used in breeding programs.

Agronomic and Physiological Constraints to the Productivity of Tropical Grain Legumes and Prospects for Improvement

1989 ◽  
Vol 25 (4) ◽  
pp. 509-528 ◽  
Author(s):  
R. J. Lawn
Keyword(s):  
Management Practices ◽  
Sowing Date ◽  
Grain Legumes ◽  
Yield Potential ◽  
Total Biomass ◽  
Short Term ◽  
Growth Duration ◽  
Productivity Improvement ◽  
Regional Effects ◽  
Physiological Constraints

SUMMARYGrowth and development of the tropical grain legumes are generally highly sensitive to photo-thermal regime, so that seasonal and regional effects on phenology and yield potential can be large. Yet failure adequately to recognize and fully exploit the consequences of genotype × latitude/sowing date × density interactions has frequently constrained both agronomic and genetic advance with these species. Thus there is opportunity for short term productivity improvements through agronomic strategies which accept the implications of phenological plasticity, and seek to optimize management practices such as sowing date and sowing density, to exploit more effectively the yield potential and broaden the adaptation of existing cultivars. The greatest physiological potential for genetic improvement in the productivity of the tropical grain legumes lies not with increasing total biomass, but with increasing the proportion of bio-mass partitioned into seed, i.e. with improved harvest index (HI). There are difficulties in selecting for higher HI, including its association with phenology, although the latter provides the most powerful tool for manipulating HI in the short term. As with the cereals, more productive genotypes are likely to be characterized by reduced sensitivity to photothermal conditions, shorter growth duration, a more synchronous reproductive ontogeny, and greater HI, than is typical of traditional cultivars. Accordingly, optimal sowing densities will be higher, and crops will need more inputs, better management and more effective protection, than afforded to them in subsistence systems of production. Moreover, the increases in productivity will be achieved, at least partially, at the expense of the potential for yield homeostasis in adverse environments, and of non-seed components such as forage, fuel or tubers - attributes that are often highly valued in subsistence agriculture where many of the tropical food legumes are presently grown. Improvement programmes will therefore need to adopt strategies in particular situations which reflect local perceptions of the importance of productivity improvement relative to that of minimizing inputs and risk.

scholarly journals Seasonal pattern of food habits of large herbivores in riverine alluvial grasslands of Brahmaputra floodplains, Assam

2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Anita Devi ◽  
Syed Ainul Hussain ◽  
Monika Sharma ◽  
Govindan Veeraswami Gopi ◽  
Ruchi Badola
Keyword(s):  
Crude Protein ◽  
Management Practices ◽  
Feeding Habits ◽  
Seasonal Pattern ◽  
Dry Season ◽  
Imperata Cylindrica ◽  
Suitable Habitat ◽  
Wet Season ◽  
Large Herbivores ◽  
Management Interventions

AbstractJarman–Bell (1974) hypothesized that in the dry savanna of Africa, small-bodied herbivores tend to browse more on forage with high protein and low fibre content. This implies browsing on high nutritive forage by meso-herbivores, and grazing and mixed feeding on coarse forage by mega-herbivores. We tested this hypothesis in the riverine alluvial grasslands of the Kaziranga National Park (KNP), where seasonal flood and fire play an important role in shaping the vegetation structure. We analyzed the feeding habits and quality of major forage species consumed by three mega-herbivores, viz. greater one-horned rhino, Asian elephant, and Asiatic wild buffalo, and three meso-herbivores, viz. swamp deer, hog deer, and sambar. We found that both mega and meso-herbivores were grazers and mixed feeders. Overall, 25 forage plants constituted more than 70% of their diet. Among monocots, family Poaceae with Saccharum spp. (contributing > 9% of the diet), and, among dicots, family Rhamnaceae with Ziziphus jujuba (contributing > 4% of the diet) fulfilled the dietary needs. In the dry season, the concentration of crude protein, neutral detergent fibre, calcium, sodium, and phosphorous varied significantly between monocots and dicots, whereas only calcium and sodium concentrations varied significantly in the wet season. Dicots were found to be more nutritious throughout the year. Compared to the dry season, the monocots, viz. Alpinia nigra, Carex vesicaria, Cynodon dactylon, Echinochloa crus-galli, Hemarthria compressa, Imperata cylindrica, and Saccharum spp., with their significantly high crude protein, were more nutritious during the wet season. Possibly due to the availability of higher quality monocots in the wet season, both mega and meso-herbivores consume it in high proportion. We concluded that the Jarman–Bell principle does not apply to riverine alluvial grasslands as body size did not explain the interspecific dietary patterns of the mega and meso-herbivores. This can be attributed to seasonal floods, habitat and forage availability, predation risk, and management practices such as controlled burning of the grasslands. The ongoing succession and invasion processes, anthropogenic pressures, and lack of grassland conservation policy are expected to affect the availability of the principal forage and suitable habitat of large herbivores in the Brahmaputra floodplains, which necessitates wet grassland-based management interventions for the continued co-existence of large herbivores in such habitats.

Socio-Economic Appraisal of Farming Households in Marginal Areas in Botolan, Zambales, Philippines

2020 ◽  
Vol 1 (1) ◽  
pp. 13-24
Author(s):  
Maria Excelsis Orden ◽  
◽  
Edwin Elane ◽  
Rhenalyn Duca ◽  
Nenita Dela Cruz ◽  
...  
Keyword(s):  
Low Income ◽  
Management Practices ◽  
High Yield ◽  
Rice Farming ◽  
Wet Season ◽  
Economic Appraisal ◽  
Marginal Areas ◽  
Production Area ◽  
Farming Households ◽  
Marginal Condition

Farm households in four barangays in Botolan, Zambales were studied to make a socio-economic appraisal of their condition after the eruption of Mt. Pinatubo in 1991 and the massive flooding in 2009 that further marginalized their farms. A self-construct questionnaire was used for 150 farming households. Socio-economic data, farm management practices, production, and income per household were described, pooled, and analyzed descriptively. As of 2018, rice farming was the main source of household income despite the land being less suitable for rice and production area reduced. There was low productivity and a high yield gap compared with the province’s and the region’s yield levels. There was high input cost in rice farming due to various factors including the marginal condition of the farms. There was low income from rice farming during both seasons, but the yield was much lower during the wet season due to lower yield.

scholarly journals Impact of Sowing Date Induced Temperature and Management Practices on Development Events and Yield of Mustard

2016 ◽  
Vol 18 (2) ◽  
pp. 45-52
Author(s):  
MSA Khan ◽  
MA Aziz
Keyword(s):  
Seed Yield ◽  
Management Practices ◽  
Agricultural Research ◽  
Sowing Date ◽  
Research Field ◽  
Yield Reduction ◽  
Sowing Dates ◽  
Mustard Crop ◽  
The Relationship ◽  
Late Sowing

The experiment was conducted at the research field of the Agronomy Division, Bangladesh Agricultural Research Institute (BARI), Joydebpur, Gazipur, during rabi season of 2014-2015 to find out the relationship between different development events of mustard crop and sowing dates induced temperature as well as to minimize the yield reduction of the crop by adopting appropriate management practices. The mustard var. BARI Sarisha-15 was sown on 06, 25 November and 14 December 2014. Crop accumulated lower growing degree days (GDD) i.e., 72.15, 521.10 and 1070 to 1154 °C were observed for the events of emergence, 50 % flowering and maturity on 14 December sowing. Late sown plants took minimum time from flowering to maturity (36 days) due to increased temperature and high variability in both maximum and minimum temperature. The highest seed yield (1569 kg ha-1) was recorded from 06 November sowing with high management practices while the lowest seed yield (435 kg ha-1) from 14 December sowing with low management practices. At high management practices the crop yielded 1183 kg ha-1 at 14 December sowing. Yield reduction at late sowing condition was reduced to some extent with high management practices. The seed yield reductions at 14 December sowing as compared to high management practices at 06 November sowing were 72, 43 and 25% under low, medium and high management, respectively.Bangladesh Agron. J. 2015, 18(2): 45-52

Genotype, sowing date and plant spacing influence on high-yielding irrigated wheat in southern New South Wales. II. Growth, yield and nitrogen use

1990 ◽  
Vol 41 (6) ◽  
pp. 1021 ◽  
Author(s):  
M Stapper ◽  
RA Fischer
Keyword(s):  
Management Practices ◽  
Maximum Yield ◽  
Sowing Date ◽  
High Yield ◽  
Yield Reduction ◽  
Grain Protein ◽  
Row Spacing ◽  
Genotypic Differences ◽  
Plant Spacing ◽  
Irrigated Wheat

Sowing date, sowing rate and row spacing effects were studied on irrigated wheat crops at Griffith, N.S.W. during 1983-85 using genotypes differing in maturity, stature and genetic background. The aim was to identify better management practices and genotypes through a better understanding of development and growth of wheat grown under high-yielding conditions. Maximum yield was up to 891 g/m2. The average yield reduction was 50 g/m2 or 6% per 1-week delay in anthesis after 1 October, but varied between 2 and 23%, depending on the season. Lodging was a significant problem in all three years, with less lodging for later sowing dates, earlier maturity types or shorter stature. Plant spacing, through variations in row spacing (17-45 cm) or sowing rate (50-200 kg/ha) did not significantly affect grain yields, but lodging was reduced by increased row spacing and reduced sowing rate. Dry weight at anthesis (600-1 500 g/m2) explained 65% of the variation in lodging, with severe lodging risks for weights over 900 g/m2. Harvest index improved with later sowing or earlier maturity and was, among genotypes within a sowing, negatively correlated with anthesis date, height, lodging score and final leaf number on the main stem. Nitrogen uptake usually ceased before anthesis. Genotypic differences in grain protein concentrations of more than 2% were found. Some genotypes combined high yield with high grain protein concentration (e.g. 717 g/m2, 14.1% protein). Significant genotype effects on spike density, kernel weight, kernel growth rate, and number of kernels per m2, per spike and per g chaff weight were identified, but none seemed to restrict yield. There was much compensation between traits. For example, high kernel numbers (per g chaff, spike or m2) were associated with low kernel weights and vice versa, both within and between genotypes. It was concluded that short-stature, early-maturing, low spike-bearing cultivars are most suited to high-yielding conditions from any sowing date, provided flowering occurs after late September, as such crops have a reduced lodging risk and use assimilates and N most efficiently. Genotypes were highly adaptable and many morphogenetic traits differed widely between genotypes, but were usually similar among dwarf or semidwarf, and among early or late maturing genotypes.

Variation in pod length in spring rape (Brassica napus) and its effect on seed yield and yield components

1989 ◽  
Vol 113 (2) ◽  
pp. 139-147 ◽  
Author(s):  
P. Chay ◽  
N. Thurling
Keyword(s):  
Seed Yield ◽  
Seed Weight ◽  
Plant Density ◽  
Unit Length ◽  
Sowing Date ◽  
High Yield ◽  
Alternative Approaches ◽  
Selection For ◽  
Pod Length ◽  
Efficient Distribution

SUMMARYTen selections from the cultivar China A, with widely different pod lengths, were compared in a single environment in Perth in 1983. Pod length was correlated positively with seed weight per pod but negatively with number of pods per plant. As a result, there was no significant relationship between pod length and seed yield, although the highest- and lowest-yielding lines were, respectively, longand short-podded.Two lines differing markedly in pod length were compared in a second experiment in 1984 in which sowing date and plant population density within a sowing date were varied. Although pod length was relatively stable, seed yield and some of its components were greatly affected by sowing date and plant density. Again, the long-podded line produced fewer pods with a greater weight of seed per pod than the short-podded line in most conditions. Compensation for greater seed weight per pod by a reduction in number of pods per plant was primarily responsible for the absence of significant differences in yield between lines in any treatment.Although long pods generally produced a greater weight of seeds per pod than short pods, the advantage in seed number and/or the weights of individual seeds was less than that expected pro rata for the much greater pod length. Indeed, short pods produced more seeds per unit length of pod than long pods. This suggested a less efficient distribution of assimilates within the longer pods, a greater amount being required to support the growth of pod walls than in short pods.Alternative approaches to using pod length as a criterion of selection for high yield are discussed.

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