Changes in leaflet shape and seeds per pod modify crop growth parameters, canopy light environment, and yield components in soybean

Reproductive development and yield components in indeterminate soybean as affected by post-flowering photoperiod

Field studies were conducted in 1984 and 1985 using non-weighing lysimeters of 1 m2 to determine the effect of level of soil moisture stress (L) and timing of moisture stress (T) on reproductive phenology, plant characteristics, and yield components of Maple Amber soybean [Glycine max (L.) Merr.]. The study incorporated the most probable combinations of moisture stress in order to provide a basis for planning and managing irrigation for optimum soybean production. The effect of L was consistent over T and Year. Neither L nor T affected days to full bloom stage (R2). Increases in L linearly (r2 = 0.71) increased days to beginning seed stage (R5), but decreased (r2 = 0.93) days to full maturity stage (R8). L was related quadratically to plant height (r2 = 0.88) and number of pod-bearing nodes (r2 = 0.98), and linearly to number of pods (r2 = 0.75) and total dry matter (r2 = 0.91). No consistent effect of T on the timing of R5 to R8 stages was found, mainly because of the presence of a Year X T interaction (P = 0.05). Withholding irrigation during the R5 stage from previously adequately watered crops caused significant reduction in plant height (7%), number of pod-bearing nodes on the main stem (13%), number of pods (18%), number of seeds (20%), total seed weight (25%), and total dry matter (23%), indicating the importance of irrigation during this stage. It was concluded that, if irrigation water is limiting, with-holding irrigation at R2 may be acceptable, but irrigation at R5 is essential for optimizing yield components and thus yield.

A field experiment was conducted at the research field of Faculty of Agriculture and Natural Resources Management, Ebonyi State University Abakaliki during the 2018 farming season to determine the effect of plant density on growth, yield and yield components of groundnut varieties. The experiment was conducted in a 3x4 factorial laid out in a randomized complete block design (RCBD). The treatments comprised three groundnut varieties (SAMNUT 24, 25 and 26) and four planting densities (40,000, 80,000, 120,000, and 160,000 plants ha-1). Each treatment was replicated four times. The parameters measured were plant height, number of leaves per plant, number of branches per plant, days to 50% flowering, shoot dry weight, leaf area index, crop growth rate, relative growth rate, net assimilation rate, number of pod per plant, pod weight per plant, hundred seed weight, number of seeds per plant, shelling percentage and total yield per hectare. The results showed that groundnut varieties were significant in all growth and yield parameters assessed except number of days to 50% flowering, Relative Growth Rate, number of pod per plant, and hundred seed weight while planting density recorded significant effect on all the growth and yield parameters. There were also significant interaction effects of varieties and plant density on plant height, number of branches per plant, leaf area index, relative growth rate, pod weight per plant, number of seeds per plant, and total yield per hectare. This result indicated that SAMNUT 26 and plant density of 160,000 plants ha-1 recorded the highest yield of groundnut and can be recommended for the farmers in the study area.

A research on the influence of a sowing date on the soybean yield and the yield of its components was carried out at the Experimental Site of the Faculty of Agriculture of the University of Zagreb during 2019 and 2020. The study involved two soybean varieties, the AFZG Ana (maturity group 0) and Gabriela (maturity group 00-0), sown on the two sowing dates (i.e., an optimal and a late one) and three sowing rates: 40, 65, and 90 germinating seeds m-2. The sowing time did not have a significant effect on the soybean seeds’ yield and the yield of their components. In both research years, the Gabriela variety achieved a higher seed yield when compared to the AFZG Ana variety, which is a result of a higher number of nodes on the main stem, number of fertile nodes on the main stem, number of pods, number of seeds, and the seed weight per plant. The Gabriela variety achieved a significantly higher harvest index in both years. The seed yield increased with an increasing sowing density up to 65 seeds m-2. However, the differences were statistically significant only in 2019. The values of the yield components decreased with an increasing sowing density.

The present investigation was undertaken to study the genetics of yield and yield components in soybean through generation mean analysis. Three crosses viz., MACS-450 × Monetta, DS-9712 × Kalitur and MACS-450 × Kalitur were made involving four parents during kharif 2013 to study the gene action for ten characters in soybean. Six generations (P 1 , P 2 , F 1 , F 2 , B 1 and B 2 ) were obtained by intermating diverse parents. Dominant gene action was observed in the inheritance of yield and yield contributing characters viz ., number of pod per plant, 100 seed weight and yield per plant. Both additive and non-additive gene effects were significantly involved in the expression of number of pods per plant (cross II), number of clusters per plant (cross II and III) and all three crosses expressed duplicate epistasis for yield per plant. Bi-parental mating design may be used to improve these characters. Complementary epistasis was observed for the cross Kalitur × DS-9712 for plant height (cm) and cross Kalitur × MACS 450 for number of pods per plant, which suggested that the selection will be practiced in F 3 generation onwards for improvement of these characters.

Effects of micronutrients [molybdenum (Mo), boron (B), iron (Fe), zinc (Zn), manganese (Mn) and copper (Cu)] on seed yield and yield components (seed yield per unit area, fertile shoots per unit area, number of racemes per shoot, number of pods per raceme, number of seeds per pod and 1000-seed weight) of alfalfa were investigated in the northwest region of China, over two seasons (2003–2004) on a torrifluvent soil and a site of 1720 m altitude. After two years study, it demonstrated that molybdenum and boron were more critical for alfalfa seed production. Molybdenum increased seed yield by 27–47%, the number of racemes per shoot by 38–55%, the number of pods per raceme by 100–133%, the number of seeds per pod by 48–61% and 1000-seed weight by 24%, and boron increased seed yield by 22–35%, fertile shoots per unit area by 17–35%, the number of racemes per shoot by 38–64%, the number of pods per raceme by 100%, the number of seeds per pod by 41–52% and 1000-seed weight by 16%. Iron, manganese, and copper had any effect on yield components, but they had no effect on seed yield. Zinc had no positive effect on seed yield and yield components. Among seed yield components, the number of pods per raceme was the most important factor to determine alfalfa seed yield. Results from this study will be used to recommend further evaluation of molybdenum and boron across a number of environments around the world and as a basis for developing recommendations to the alfalfa seed production industry.

An experiment with sixteen cropping systems (pure and intercroppings) was conducted during the kharif season of 1985 and 1986. The sixteen cropping systems were: sole rice, sole mungbean, sole soybean, sole peanut, sole blackgram, rice + mungbean (2:1), rice + mungbean (4:1), rice + mungbean deferred (2:1), rice + soybean (2:1), rice + soybean (4 : 1), rice + soybean deferred (2 : 1), rice + peanut (2:1), rice + peanut (4 : 1), rice + blackgram (2:1), rice + blackgram (4:1) and rice + blackgram deferred (2:1). Sole crop of rice always recorded higher number of effective tillers/m2, however, it was observed that legumes had an influence on the number of filled grains per panicle and thousand grain weight of rice in rice + legume combinations. Among legumes, pure crops of soybean and peanut always gave rise to increased number of yield components than the other crops grown in association with rice. In case of mungbean, number of pods per plant and thousand seed weight was higher in pure crops though number of seeds per pod was more with rice + mungbean combination. Deferred sown blackgram in association with rice yielded greater number of seeds per pod and thousand seed weight though sole crop of blackgram significantly produced higher number of pods per plant.

The number of pods per unit area is an important component of pod yield of peanut. The goals of this study were to determine the relationships of (i) pod yield with number of pods per unit area and weight per pod and (ii) number of pods per unit area with crop growth rate (CGR) and duration during the different developmental stages. Fifteen peanut lines were tested at Khon Kaen University in Northeast Thailand during the 2002 and 2003 rainy and the 2003 and 2004 dry seasons. Data were recorded on developmental stages, biomass, pod yield, and yield components. The CGRs were calculated for different developmental periods. Results showed a positive linear relationship between pod yield and number of pods per unit area across genotypes and seasons (R2 = 0.69; P > F < 0.0001), but no relationship was observed between pod yield and weight per pod (R2 = 0.001; P > F = 0.85). A significant relationship between number of pods per unit area and CGR among the test genotypes was found only during the period from R6 to R7 (R2 = 0.44; P > F = 0.007), and the same relationship across seasons was significant (R2 = 0.45; P > F < 0.001) only during the period from planting to R4. These results indicate that number of pods per unit area is the major determinant for pod‐yield differences among peanut lines, and that the differences among lines for this trait are influenced by CGR during the period from R6 to R7.

An analysis was carried out during 2007-2009 on nine spring-sown Bulgarian and Ukrainian field pea cultivars. Strongest positive phenotypic correlations were observed between number of fertile nodes per plant and numbers of pods (r = 0.97) and number of seeds per plant (r = 0.97) and between number of seeds and pods per plant (r = 0.94); between seed weight per plant and number of seeds (r = 0.83) and fertile nodes per plant (r = 0.77). High genetic correlations were found between plant height and first pod height (r = 0.89), between number of pods per plant and seed weight per plant (r = 0.91) and number of seeds per plant (r = 0.96) and between seed weight per plant and number of branches per plant (r = 0.92) and number of fertile nodes per plant (r = 0.89). The strongest and direct positive effect on seed yield was found in branch length (17.70), 1000-seed weight (5.92) and number of seeds per pod (4.93). The highest positive indirect contribution was in branch length to number of seeds per pod (2214.8), number of fertile nodes per plant (1258.0) and number of seeds per plant (708.70). Based on the trait association and the path coefficients for seed yield and its components, it can be concluded that field pea breeders should pay attention to traits such as branch length, 1000-seed weight and number of seeds per pod when selecting high-yielding genotypes in field pea.

One common approach to increase crop production is through multiple cropping systems. This study was conducted to (1) evaluate the growth and yield of peanut as influenced by time of planting sweetpotato as intercrop; (2) determine the appropriate time of planting peanut and sweetpotato that would give their respective optimum yields; and (3) determine the profitability of growing peanut in combination with sweetpotato as influenced by time of planting the crops in an intercropping scheme. Results of the study showed that peanut’s maturity, leaf area index (LAI), number of seeds pod and number of pods plant were significantly (p<0.05) increased by the time of planting sweetpotato as intercrop. Sweetpotato planted later than peanut significantly (p<0.05) improved the number of lateral vines plant, length of main vine, and fresh herbage yield of sweetpotato. Yield and yield components and harvest index of sweetpotato were not significantly (p <0.05) affected by the time of planting the crops. A net income of Php 66,508.00 was obtained from plots planted with peanut + sweetpotato regardless of time of planting. All intercropping treatments had a leaf area index (LER) of greater than one which means that peanut and sweetpotato are a good combination in an intercropping scheme compared to planting peanut as monocrop.

Leaf spot and rust are two important diseases on groundnut. Both diseases are frequently found at the same time that influence the growth and reduce the yield of groundnut. This study was conducted to evaluate thirteen groundnut genotypes resistance to leaf spot and rust disease. The experiment was conducted using a split plot design and three replications, with inoculated and uninoculated treatment as main plot, and groundnut genotypes as the sub plot. Disease assessment was conducted by counting number of pustules per leaf, the number of spots per leaf, rust disease intensity, the intensity of leaf spot disease, and leaf area index. Yield components including stover weight, number of pods per plant, number of empty pods, number of chipo pods, and weight of pods per plant were recorded for both inoculated and uninoculated plants. The result showed that leaf spot disease developed earlier than rust disease. Only one genotype was susceptible to rust and the other 12 genotypes were very susceptible, whereas all genotypes tested were very susceptible to leaf spot. The intensity of rust and leaf spot diseases was negatively correlated with yield (r = - 0.1 – (0.4)). Rust and leaf spot diseases reduced the yield components including stover weight (73.2%), number of pods (68%), and weight of pods (72.5%). The number of empty pods and chipo pods were increase to 81% and 56.4% respectively.

Weed infestation is a major cause of the poor yield of soybeans (Glycine max (L.) Merr.); therefore, proper weed management represents one of the most important and expensive steps in soybean production. Field experiments were established in northeastern parts of Croatia, in the Vukovar-Syrmia county from 2014 to 2016, arranged in a split-plot design with four replications. Two different studies were conducted: the first study was to determine the weed interference, weed biomass accumulation, yield, and yield components of soybeans growing in three different rows spacing (25, 50, and 70 cm), and the second study aimed to simulate a risk analysis by building models of probabilities for generating profit as a result of weed control. The weed community in soybean during the study period comprised 34 dicot and grass species of a varied perennation. Compositional differences in the weed community tended to be affected most by the year (humid–arid environment), followed by row spacing. There were no differences in the weed biomass accumulation with a reduction in row spacing from 70 to 50 and 25 cm. The dominant weed species Amaranthus retroflexus, Ambrosia artemisiifolia, Chenopodium album, Datura stramonium, Setaria viridis, and Sorghum halepense formed the main biomass and were spread over all row spacings. There was a significant influence of row spacing, the duration of weed interference, and year on soybean yield and yield components. Weed infestation until the second trifoliate (V2) stage had no detrimental effect on soybean yield, regardless of the row spacing. The number of pods per plant significantly decreased at the same V2 stage in 25 and 50-cm rows, but in 70-cm soybean rows, this process started later, at four unfolded trifoliate leaves (V4 stage). A 1000 kernel weight was less sensitive to weed infestation and was significantly decreased at full flowering (R2 stage) in 25 and 70 cm rows, while it already decreased at the V4 stage in 50 cm rows. The probability distribution of achieving a profit showed the best results for soybeans growing in 70 cm rows, with preemergence herbicide application and two inter-row cultivation.

In order to investigate the effect of weed control with common herbicides on yield and components of soybean yield (Glycin max L.) in the second crop, two experiments were conducted as a randomized complete block design with three replications at the Agricultural and Natural Resources Research Center of Moghan during 2016-2017 and 2017-2018. The treatments consisted of Ethalfluralin, Imazethapyr, Trifluralin, Metribuzin, Bentazone and Alacolor herbicides with and without weed control. The results showed that the number of pods per plant, biological yield, grain yield and soybean protein percentage were statistically significant, but for chlorophyll index, 1000 seed weight and oil percent grain, the difference was not statistically significant. The highest number of pods per plant (333.92), biological yield (1221 g.plant-1) and grain yield (2792 kg.ha-1) were obtained from hand weeding. The results of the analysis of variance showed that the treatments had a significant difference in terms of the percentage of the effect of herbicide, density and total weed dry weight. The results showed that one month after spraying, the Trifluralin and Ethalfluralin herbicides had the highest effect on the weed control and two months after spraying, the rest of the treatments also showed their effect and all herbicide treatments were in one group. In this study, all weed control treatments significantly reduced the density and dry weight of weeds than without control, but their effect was less than hand weeding. The highest grain yield (1896 kg.ha-1) and the highest biological yield (784.9 kg.ha-1) were observed from Ethalfluralin herbicide

In the paper, the effect of different shading treatments (full sunlight, light shading: 40%, medium shading: 75%, and heavy shading: 90%) on yield and crop growth parameters of vining pea was investigated. The experiment was conducted at Dicle University, Faculty of Agriculture, in Diyarbakir, T?rkiye during the 2023 spring season under field conditions. The experiment was arranged Randomized Complete Blocks design with three replications. In study, some observations were investigated such as plant height, number of internodes per plant, leaf area per plant, number of leaves per plant, dry matter, SPAD value, soil moisture, number of pods per plant, fresh pod weight, pod width, pod length, number of seeds per pod and dry pod weight and some growth parameters were calculated. For this purpose, plants were harvested six times at 10-day intervals and measured for growth and yield parameters. Consequently, shading treatments increased fresh pod weight, pod width, and pod length compared to full sunlight, while heavy shading (90%) significantly reduced plant height. The crop growth rate tended downward under the shading conditions at the blooming and podding stages. However, crop growth rate was apparently higher under low light intensity (light shading; 6.46 g m-2 day-1 and heavy shading; 5.14 g m-2 day-1) than at full sunlight (3.35 g m-2 day-1) at the podding stage. Full sunlight was the most sensitive treatment to environmental conditions, therefore, the relative growth rate drastically reduced during the crop growth stages. In conclusion, the relative growth rate of crops grown under full sunlight was significantly lower than that of crops grown under other treatments. In summary, light and temperature accelerated crop development under full sunlight, while shade applications extended crop development duration. As a result, medium and low-level shading is thought to extend crop vegetation duration, especially in the arid and semi-arid climate areas exposed to water scarcity and high heat.

Field experiments were conducted in 2017 early and late cropping seasons at National Cereals Research Institute, Uyo Out Station, Owot Uta, Ibesikpo Asutan LGA of Akwa Ibom State to determine variability, seasonal effects and principal components of growth characters, yield and yield components of seven cowpea genotypes. The experiments were laid out in a randomized complete block design in four replications. Fourteen characters were studied namely; percentage establishment (%), plant height (cm), number of leaves, leaf area (cm2), number of branches per plant, days to first flowering, days to 50% flowering, length of pods (cm), girth of pods (cm), number of pods per plant, number of seeds per pod, weight of pods (g), weight of 100 seeds (g) and seed yield (kg/ha). Significant differences (p<0.05) were observed among the cowpea genotypes in plant height, number of leaves, number of branches per plant, number of pods per plant, number of seeds per pod and seed yield (kg/ha). The cowpea genotypes IT89KD391B was superior in 5 characters, namely plants heights (cm), number of leaves, leaf area (cm2), length of pods (cm), girth of pods and weight of 100 seeds, followed by Ife brown for days to first flowering, days to 50% flowering, number of pods per plant, number of seeds per pod and seed yield (kg/ha) while IT89KD260 recorded the highest percentage establishment and number of branches per plant. First 4PC with Eigen values greater than 1.0 jointly explained 89.3% of the total variations in the genotypes. Significant seasonal effects were observed on plant height, number of leaves, number of branches, number of pods, number of seeds per pod, and seed yield (kg/ha). The result identified late cropping season as the best season for cowpea production in Uyo, Southern Nigeria.