Agronomic studies on pigeon pea (Cajanus cajan (L.) Millsp.) III.* Responses to defoliation

1975 ◽  
Vol 26 (1) ◽  
pp. 67 ◽  
Author(s):  
JO Akinola ◽  
PC Whiteman

Two early-maturing and two late-maturing accessions of Cajanus cajan grown in the field for 161 days were defoliated to 90 cm 'stubbles' every 4,8,12 or 16 weeks over a period of 72 weeks. Evidence from total and seasonal dry matter and nitrogen yields, stand survival, and stubble yield at the termination of the experiment suggested that 8- and 12-week defoliation frequencies could be successfully integrated to incorporate cattle grazing and forage and seed production into a single management system. The late-maturing accessions were shown clearly to be better adapted to cutting, provided that basal green leaves always remained on the stubble. Defoliation of the accession UQ50 to reduce plant height to facilitate subsequent harvesting led to a reduced annual seed yield. The first seed crop was lost, as 'topping' removed the reproductive material.

1975 ◽  
Vol 26 (1) ◽  
pp. 57 ◽  
Author(s):  
JO Akinola ◽  
PC Whiteman

Vegetative and seed yield in Cajanus cajan accession UQ1 were investigated over nine sowing densities ranging from 6727 to 215,278 plants per hectare. Dry matter yield per plant declined asymptotically with increasing density, while the yield per hectare v. density relationship was described by a parabolic curve. The highest yield per hectare (22,950 kg) was produced at the 0.305 by 0.305 m spacing (107,639 plants ha-1). Maximum seed yield (2774 kg ha-1) was attained at a relatively low density at a spacing 0.914 by 0.610 m (17,940 plants ha-1). At higher densities, increased stand mortality and reduced numbers of pods per plant resulted in severe yield reductions. Reduced pod number per plant was related to significant reductions in the number of pod-producing branches and the inflorescence-bearing stem length, with little change in seed size or seeds per pod. Interactions of yield components, leaf area index, and other plant parameters are discussed. *Part I, Aust. J. Agric. Res., 26: 43 (1975).


Author(s):  
N. Borah ◽  
A. Sarma ◽  
D. Sarma ◽  
A. Bhattacharjee ◽  
D. Bordoloi

The present investigation was undertaken with the objective to estimate the interrelationship of characters for seed yield in early maturing genotypes of pigeon pea (Cajanus cajan L.). The material consisted of twenty-one pigeon pea genotypes among which nineteen were early maturing genotypes received from ICRISAT (The International Crops Research Institute for the Semi-Arid Tropics), Hyderabad and two were local varieties collected from BNCA, AAU (Biswanath Chariali College of Agriculture, Assam Agricultural University), Jorhat. The experiment was conducted during kharif 2017-18 in randomized block design (RBD) with three replications at ICR farm, Assam Agricultural University, Jorhat. The estimates of genotypic correlations, in general, were found higher than the corresponding phenotypic correlation coefficients indicating strong association between two characters but the phenotypic values were lessened by the influence of environment. The seed yield per plant had shown significant positive correlation with plant height, pods per plant, pod length and harvest index both at phenotypic and genotypic level. Pods per plant and pod length had shown high positive direct effects on seed yield per plant at both genotypic and phenotypic level. At genotypic level, days to first flowering exhibited maximum positive direct effect on seed yield per plant. Pods per plant and pod length had shown high direct effects on seed yield/plant and hence direct selection for these traits may contribute towards improvement in seed yield/plant.


Author(s):  
Muhammad Zeeshan Mehmood ◽  
Ghulam Qadir ◽  
Obaid Afzal ◽  
Atta Mohi Ud Din ◽  
Muhammad Ali Raza ◽  
...  

AbstractSeveral biotic and abiotic stresses significantly decrease the biomass accumulation and seed yield of sesame crops under rainfed areas. However, plant growth regulators (such as Paclobutrazol) can improve the total dry matter and seed production of the sesame crop. The effects of the paclobutrazol application on dry matter accumulation and seed yield had not been studied before in sesame under rainfed conditions. Therefore, a two-year field study during 2018 and 2019 was conducted with key objectives to assess the impacts of paclobutrazol on leaf greenness, leaf area, total dry matter production and partitioning, seed shattering, and seed yield of sesame. Two sesame cultivars (TS-5 and TS-3) were treated with four paclobutrazol concentrations (P0 = Control, P1 = 100 mg L−1, P2 = 200 mg L−1, P3 = 300 mg L−1). The experiment was executed in RCBD-factorial design with three replications. Compared with P0, treatment P3 improved the leaf greenness of sesame by 17%, 38%, and 60% at 45, 85, and 125 days after sowing, respectively. However, P3 treatment decreased the leaf area of sesame by 14% and 20% at 45 and 85 days after sowing than P0, respectively. Compared with P0, treatment P3 increased the leaf area by 46% at 125 days after sowing. On average, treatment P3 also improved the total biomass production by 21% and partitioning in roots, stems, leaves, capsules, and seeds by 23%, 19%, 23%, 22%, and 40%, respectively, in the whole growing seasons as compared to P0. Moreover, under P3 treatment, sesame attained the highest seed yield and lowest seed shattering by 27% and 30%, respectively, compared to P0. This study indicated that by applying the paclobutrazol concentration at the rate of 300 mg L−1 in sesame, the leaf greenness, leaf areas, biomass accumulation, partitioning, seed yield, and shatter resistance could be improved. Thus, the optimum paclobutrazol level could enhance the dry matter accumulation and seed production capacity of sesame by decreasing shattering losses under rainfed conditions.


2019 ◽  
Vol 17 (1) ◽  
pp. 33-38
Author(s):  
Swapan Kumar Paul ◽  
Mosa Morsheda Khatun ◽  
Md Abdur Rahman Sarkar

Sulphur is a component of plant amino acids, proteins, vitamins, and enzyme structures which influence the productivity of oil seed and total oil content. The experiment was conducted to find out the effect of sulphur on the seed yield and oil content of sesame in Bangladesh. The experiment comprised three varieties of sesame viz. Binatil-2, Binatil-3 and BARI Til-4 and six levels of sulphur (S) viz. 0, 10, 20, 30, 40 and 50 kg S ha–1. The experiment was laid out in a randomized complete block design with three replications. Dry matter production, crop characters, yield components, seed yield and oil content were significantly influenced by variety, level of sulphur and their interaction. The highest dry matter production plant–1 at 50 DAS (17.56 g), plant height (101.3 cm), number of branches plant–1 (3.66),  number of pods plant-1 (41.56), number of seeds pod-1 (58.83),  seed yield    (747.2 kg ha-1), stover yield (2243.0 kg ha–1) and oil content (40.03%) were obtained in BARI Til-4 while the corresponding lowest values of all parameters were recorded in Binatil-2. In case of sulphur application, the highest dry matter production plant–1 at 50 DAS (20.81 g), plant height (109.7 cm), number of branches plant–1 (3.87),  number of pods plant–1 (46.13),  number of seeds pod-1 (56.67),  seed yield (800.0 kg ha–1), stover yield (2787 kg ha–1 ) and oil content (43.97%) were obtained when crop was fertilized with 30 kg S ha–1 while the lowest seed yield (502.2 kg ha–1), stover yield (1550.0 kg ha–1) and oil content (32.80%) were obtained in control (0 kg S ha–1). BARI Til-4 fertilized with 30 kg S ha–1 produced the highest dry matter plant–1 at 50 DAS (24.80 g), number of pods plant–1 (51.13), seeds pod–1 (62.0) and seed yield (1011.0 kg ha–1). The highest oil content (43.97%) was also recorded in BARI Til-4 fertilized with 30 kg S ha–1, which was as good as that of BARI Til-4 fertilized with 40 kg S ha–1. Therefore, BARI Til-4 fertilized with 30 kg S ha–1 can be considered as a promising practice in respect of seed yield and oil content of sesame in Bangladesh. J. Bangladesh Agril. Univ. 17(1): 33–38, March 2019


2020 ◽  
Vol 50 (9) ◽  
Author(s):  
Alfredo Junior Paiola Albrecht ◽  
Leandro Paiola Albrecht ◽  
André Felipe Moreira Silva ◽  
Romulo Augusto Ramos ◽  
Natália Buttini Corrêa ◽  
...  

ABSTRACT: Conyza spp. is among the main weeds reported worldwide. Due to its aggressiveness, such as high seed production and dispersion, and the growing reports of biotypes resistant to glyphosate, paraquat, and other herbicides, different control practices are required. Thus, this study aimed to evaluate the efficacy of herbicides with sequential application of glufosinate in soybean pre-sowing for control of Conyza spp. with indicative of resistant to paraquat. The study was carried out in the field, at Assis Chateaubriand and Palotina, state of Paraná, Brazil, in the 2018/19 season. The experiments were conducted in a randomized block design with four replications. The treatments consisted in application of glyphosate, 2,4-D, saflufenacil, glufosinate, saflufenacil/imazethapyr, diclosulam, paraquat/diuron, paraquat and imazethapyr/flumioxazin, at different combinations, in soybean pre-sowing. Control of Conyza spp., crop injury to soybean plants and variables related to agronomic performance (plant height and yield) were evaluated. All treatments were selective for soybean, which showed stronger crop injury in the presence of diclosulam herbicide, but this did not compromise soybean agronomic performance. In general, control levels were high for the treatments used. Except for paraquat treatments, in the area with the highest frequency of Conyza spp. with indicative of resistant to paraquat, and imazethapyr/flumioxazin treatment in both areas. These control results emphasized the importance of glufosinate in this management system and showed promising results for saflufenacil/imazethapyr.


1985 ◽  
Vol 104 (3) ◽  
pp. 589-593 ◽  
Author(s):  
T. O. Tayo

SummaryPigeon pea (variety Cita-1) was sown on ridges at two plantings in the early and late seasons of 1983 at the University of Ibadan, Two to three weeks after the plants reached maturity and the pods had been harvested by hand-picking, the plants were either ratooned by cutting off the tops at a height of 30 and 60 cm or left intact.At the end of the first and second regrowths, the plants ratooned at 30 and 60 cm had performed better than those left intact in terms of growth and yield characters as well as seed yield. However, the plants ratooned at 30 cm performed best followed by those ratooned at 60 cm. The total seed yield from the planting was 3–6 times higher than if the crop had been harvested once.It would seem that ratooning at 30 cm would give the highest returns from a single planting under the prevailing lowland tropical conditions.


1984 ◽  
Vol 35 (4) ◽  
pp. 511 ◽  
Author(s):  
RW Downes ◽  
JS Gladstones

Plants of Lupinus angustifolius cv. Unicrop were raised at 27/22 or 21/16�C dayhight temperatures until flowering. They were then either grown on to maturity at these conditions or moved to the other regime. Branches were removed as they started to develop and leaves were removed at the start of flowering so that 0, 3, 6, 9, 12 upper leaves or all 21 leaves were retained. Conditions before flowering determined potential pod number. Defoliation treatments revealed that under favourably cool conditions all leaves contributed to seed yield but in treatments involving 27/22'C there was no seed yield response to more than about six leaves, emphasizing the significance of environmental conditions rather than current assimilate on pod set and other yield components. In another experiment, plants were raised to flowering at 27/22, 21/16 or 15/10�C before flowering, when all were moved to 21/16�C. Half the plants were allowed to develop branches and on the remainder branch buds were removed. Branch and stem growth appeared to provide severe competition for the development of the primary inflorescence. Though branching was much more pronounced in plants at 15/10�C before flowering than in other treatments, vegetative development exceeded reproductive investment and harvest index was low under these conditions. It was suggested that there appears to be a need to develop and evaluate unbranched or less-branched lupin genotypes.


2016 ◽  
Vol 50 (3) ◽  
Author(s):  
R. S. Singh ◽  
M. N. Singh

The six generations (P<sub>1</sub>, P<sub>2</sub>, F<sub>1</sub>, F<sub>2</sub>, BC<sub>1</sub> and BC<sub>2</sub>) of twelve cross combinations of pigeonpea (<italic>Cajanus cajan</italic> L.) were studied during 2003-2006 for days to 50 % flowering, days to maturity, plant height, number of primary branches, number of secondary branches, pods per plant, pod length, number of seeds per pod, 100-seed weight, harvest index and seed yield per plant. The means of six generations were subjected to detect main gene effects and interactions. The estimates of six parameter model revealed that both additive and dominant gene effects were important in all the crosses for almost all the traits. However, the relative contribution of dominant gene effects was much higher than additive gene effects for plant height, pods per plant and seed yield per plant. Higher frequency of duplicate type of epistasis also confirms the prevalence of dominance gene effects for above traits except for seed yield per plant.


Author(s):  
Rupinder Kaur Jassal ◽  
Harmeet Singh

An experiment was conducted at Punjab Agricultural University, Ludhiana during 2015 and 2016 to study the effect of priming, different seed rate on growth and seed yield of soybean planted under bed and flat method. The study was planned in factorial split plot design, keeping two planting techniques (flat sowing and bed sowing) and two seed priming treatments ( non primed seeds and 100 ppm GA3 primed seeds) in main plot and three seed levels ( 50, 62.5 and 75 kg ha-1) in sub plot. The objective of the study was to evaluate the effect of seed priming on growth and productivity under different planting techniques with the use of varying seed rates. The results revealed that growth attributes viz. emergence count, plant height, dry matter accumulation, leaf area index and photosynthetic active radiation interception (%) was significantly higher under bed planting technique as compared to flat sowing method. The pooled seed yield was increased by 15.6 % in bed planted soybean crop as compared to flat planted crop. Soybean seeds primed with 100 ppm GA3 recorded significant results in all the growth parameters. Primed seed recorded increase in yield 15.3 % than non primed seeds. Seed rate of 62.5 kg ha-1 recorded significantly higher emergence count, plant height, dry matter accumulation, leaf area index and photosynthetic active radiation interception (%) which was statistically similar in results with 75 kg ha-1 seed rate in both the two years. Pooled seed yield of 62.5 kg ha-1seed rate was 4.61 % higher than 75 kg ha-1 and 12.6 % than 50 kg ha-1 seed rate.


1989 ◽  
Vol 40 (4) ◽  
pp. 833
Author(s):  
JD McFarlane

Seven rates of copper were applied to the soil prior to the sowing of strawberry clover (Trifolium fragiferumL. cv. Palestine) on an alkaline peat deficient in copper. Symptoms of copper deficiency were evident only on the untreated plots where the clover did not set seed nor persist into the second year.Over five years� production, 1.0 kg Cu/ha continued to provide adequate copper, with regular dressings of superphosphate, for maximum dry matter production and seed yield. It was found that seed yield was more sensitive than vegetative dry matter yield to sub-optimal copper supply. At the lowest rate of applied copper (0.125 kg/ha), the vegetative yield ranged from 53% to 80% of the maximum harvest yield, whereas the seed yield ranged from 15% to 50% of maximum yield.For tissue sampled in the spring, the proposed critical range for copper concentration in the youngest open leaf (YOL) for vegetative dry matter production is 3-35 mg Cu/kg whereas that for seed production is 4.5-5.5 mg Cu/kg. At other times of the year the critical concentrations were higher. It was not clear if this was due to environmental conditions or changing internal requirements for copper.The critical copper concentration range in whole top (WT) tissue of 3.0-4.0 mg/kg for vegetative dry matter production could be applied to all samplings. For seed yield the critical range for copper concentration in WT was 4.0-5.0 mg/kg for the spring harvests. The critical copper concentration in seed for seed production was 5.0-6.0 mg/kg. In the pasture situation a critical concentration of 5.0-6.0 mg Cu/kg in the WT should be adopted when the animal requirement is considered.


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