Adaptation of soybean (Glycine max (L.) Merrill) to the dry season of the tropics. II. Effects of genotype and environment on biomass and seed yield

1991 ◽  
Vol 42 (3) ◽  
pp. 517 ◽  
Author(s):  
JD Mayers ◽  
RJ Lawn ◽  
DE Byth

Eight soybean genotypes were sown at weekly intervals in three tropical dry season environments to examine genotypic and environmental effects on growth and seed yield per plant. In general, dry matter (DM) at maturity increased exponentially with crop duration and so was greater with later maturing genotypes and sowing dates where photothermal conditions slowed development. Across environments, thermal time provided a better description of DM accumulation than did crop duration, indicating direct effects of temperature on growth rates. Among genotypes, the relationship between seed yield and DM production was strongly linear, implying that under the wide spacings of the study, DM production was the main basis of genotypic differences in seed yield. Among environmental means, the relationship was both weaker and curvilinear, suggesting that environmental effects on vegetative growth were not necessarily reflected in seed yield. Further, where photothermal regime delayed flowering and maturity, vegetative growth was often excessive, and harvest index (HI) smaller. HI was also smaller where flowering coincided with cool night temperatures (< c. 14�C) and podset was reduced. Overall, HI was negatively correlated with crop duration. Responses are discussed in terms of the implications for soybean improvement for the tropical dry season.

1991 ◽  
Vol 42 (7) ◽  
pp. 1109 ◽  
Author(s):  
JD Mayers ◽  
RJ Lawn ◽  
DE Byth

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.


1966 ◽  
Vol 17 (3) ◽  
pp. 255 ◽  
Author(s):  
RA Fischer ◽  
GD Kohn

In trials conducted in 1961 and 1962 at Wagga in southern New South Wales, to investigate the yield physiology of wheat, the variety Heron was grown under various cultural treatments. This paper deals with the relationship of evapotranspiration to crop growth. Vegetative growth at a given date in the spring was influenced markedly by time of sowing and fertilizer application, and to a lesser extent by sowing rate. Large differences in vegetative growth caused relatively small differences in evapotranspiration rate when soil moisture was adequate. An increase in total dry weight of 100 g/m² in early October was associated with an increase in cumulative evapotranspiration up to that time of about 0.50 in. It was concluded that although a reduced fertilizer application and reduced sowing rate (below 3b lb seed per acre) permitted higher soil moisture levels at flowering, this necessarily involved a considerable reduction in total dry weight at flowering. With delayed time of sowing, the post-flowering moisture status of the crop can be expected to deteriorate, primarily because of delayed flowering date.


2019 ◽  
pp. 11-25

Climate change and population growth are the two most important challengers faced by today. So that, two field experiments were carried out at the Horticulture Research Farm of El- Baramoon, Dakahlia Governorate, Egypt, during the two winter seasons of 2017/2018 and 2018/2019 to evaluate the response of sweet fennel to foliar application with moringa leaf extract, seaweed extract and potassium sulphate levels in addition to control treatment under two sowing dates, i.e., 15th October and 15th November. The best results were recorded when sweet fennel seeds were sown on 15th October compared with sowing 15th November in the both tested seasons. Also, foliar spraying with seaweed, moringa leaf extracts and potassium sulphate improved vegetative growth, i.e., plant height; number of leaves and branches per plant and fresh and dry weight per plant as well as yield component, i.e., bulb length; bulb diameter; bulb thickness; seed yield, i.e., number of umbels per plant, weight of seeds per plant and weight of seeds per feddan and essential oil traits than sprayed with tap water (control) during the two seasons. The interaction between sowing dates 15th October and spraying with seaweed extract at 2 g / l resulted in higher values of studied traits in sweet fennel. Thus, we provide the evidence for sowing sweet fennel on the early date (15th October) then spraying the plants with seaweed extract at 1 and / or 2 g / l to produce higher vegetative growth, seed yield and essential oil traits in sweet fennel (Foeniculum vulgare Mill).


1991 ◽  
Vol 42 (3) ◽  
pp. 497 ◽  
Author(s):  
JD Mayers ◽  
RJ Lawn ◽  
DE Byth

Eight soybean genotpes were sown at weekly intervals in three tropical dry season environments to examine genotypic and environmental effects on phenology. A series of simple linear models was used to test the relationships, for individual genotypes, between rate of development for the vegetative (Rf) and reproductive (Rr) phases and photoperiod and temperature. For each genotype, most (> 85%) of the variation across sites, years and sowing dates in Rf and more than half the variation in Rr could be accounted for by variation in photoperiod and/or temperature. Rf was generally negatively associted with mean maximum temperature and mean photoperiod, and positively with mean minimum temperature. Rr was generally positively associated with either mean, or mean maximum, temperature and negatively with mean photoperiod. It was concluded that variations in photothermal regime across sites, years and sowing dates within the tropical dry season are sufficiently large to induce instability in time to flowering of most present soybean cultivars. Most genotypes are also poorly adapted to the relatively long day-warm temperature conditions experienced by dry season crops during podfilling, presumably because they have been developed as summer crops. Breeding soybeans for the dry season will therefore need to place strong emphasis on photothermal effects during post-flowering as well as pre-flowering development.


1977 ◽  
Vol 13 (1) ◽  
pp. 93-100 ◽  
Author(s):  
J. Y. Yayock ◽  
J. G. Quinn

SUMMARYForty-six cultivars of linseed oil (Linum usitatissimum L.) were grown under wet and dry season conditions in the Sudan Savanna of Nigeria. Only during the dry season was production good and cv Dunes consistently outyielded all other cultivars in terms of seed and oil content. Trials of sowing dates gave maximum seed yield and oil content from plots sown during late October. In row spacing trials, rows 15–22 cm apart and seed rates of 58–78 kg/ha were found to be the most practicable. There was a linear relation between increasing rates of nitrogen and seed yield, maximum production being obtained at 55–88 kg N/ha, but oil content was slightly depressed at levels above 33 kg N/ha.


2016 ◽  
Vol 18 (2) ◽  
pp. 45-52
Author(s):  
MSA Khan ◽  
MA Aziz

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


2004 ◽  
Vol 52 (2) ◽  
pp. 157-163
Author(s):  
C. U. Egbo ◽  
M. A. Adagba ◽  
D. K. Adedzwa

Field trials were conducted in the wet seasons of 1997 and 1998 at Makurdi, Otukpo and Yandev in the Southern Guinea Savanna ecological zone of Nigeria to study the responses of ten soybean genotypes to intercropping. The experiment was laid out in a randomised complete block design. The genotypes TGX 1807-19F, NCRI-Soy2, Cameroon Late and TGX 1485-1D had the highest grain yield. All the Land Equivalent Ratio (LER) values were higher than unity, indicating that there is great advantage in intercropping maize with soybean. The yield of soybean was positively correlated with the days to 50% flowering, days to maturity, plant height, pods/plant and leaf area, indicating that an improvement in any of these traits will be reflected in an increase in seed yield. There was a significant genotype × yield × location interaction for all traits. This suggests that none of these factors acted independently. Similarly, the genotype × location interaction was more important than the genotype × year interaction for seed yield, indicating that the yield response of the ten soybean genotypes varied across locations rather than across years. Therefore, using more testing sites for evaluation may be more important than the number of years.


Agronomy ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 574
Author(s):  
Yun-Yin Feng ◽  
Jin He ◽  
Yi Jin ◽  
Feng-Min Li

Both water stress and P deficit limit soybean seed yield, but the effects of water regimes and P application rates, their interaction on P status, acquisition, and partitioning, and their roles in yield performance have not been well-studied. Two soybean genotypes (Huangsedadou (HD) and Zhonghuang 30 (ZH)) with contrasting seed yield and root dry weight (DW) were used to investigate the P status, P acquisition, P partitioning, and yield formation under two water regimes (well-watered (WW) and cyclic water stress (WS)) and three P rates (0 (P0), 60 (P60), and 120 (P120) mg P kg−1 dry soil). The results show that increased P and water supply increased the seed yield, shoot and root DW and P concentrations and accumulations in different organs. Cultivar ZH had a significantly higher seed yield than HD at P60 and P120 under WS and at P0 under WW, but a lower seed yield at P60 and P120 under WW. Cultivar ZH had a significantly higher P harvest index and P acquisition efficiency, but a significantly lower shoot and root DW than HD. The interaction between water treatments and P rates had significant effects on leaf and stem P concentration. Cultivar ZH had significantly lower P partitioning to leaves and stems but significantly higher P partitioning to seeds than HD. The seed yield was positively correlated with leaf and seed P accumulations and P acquisition efficiency under WS. We conclude that (1) adequate water supply improved the P mobilization from leaves and stems at maturity, which may have improved the seed yield; and (2) the high P acquisition efficiency is coordination to high P partition to seeds to produce a high seed yield under water- and P-limited conditions.


2011 ◽  
Vol 62 (1) ◽  
pp. 1 ◽  
Author(s):  
R. J. Lawn ◽  
A. T. James

The purpose of this paper and its companion1 is to describe how, in eastern Australia, soybean improvement, in terms of both breeding and agronomy, has been informed and influenced over the past four decades by physiological understanding of the environmental control of phenology. This first paper describes how initial attempts to grow soybean in eastern Australia, using varieties and production practices from the southern USA, met with limited success due to large variety × environment interaction effects on seed yield. In particular, there were large variety × location, variety × sowing date, and variety × sowing date × density effects. These various interaction effects were ultimately explained in terms of the effects of photo-thermal environment on the phenology of different varieties, and the consequences for radiation interception, dry matter production, harvest index, and seed yield. This knowledge enabled the formulation of agronomic practices to optimise sowing date and planting arrangement to suit particular varieties, and underpinned the establishment of commercial production in south-eastern Queensland in the early 1970s. It also influenced the establishment and operation over the next three decades of several separate breeding programs, each targeting phenological adaptation to specific latitudinal regions of eastern Australia. This paper also describes how physiological developments internationally, particularly the discovery of the long juvenile trait and to a lesser extent the semi-dwarf ideotype, subsequently enabled an approach to be conceived for broadening the phenological adaptation of soybeans across latitudes and sowing dates. The application of this approach, and its outcomes in terms of varietal improvement, agronomic management, and the structure of the breeding program, are described in the companion paper.


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 ◽  
...  

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.


Sign in / Sign up

Export Citation Format

Share Document