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Growth and yield of common bean cultivars at two soil phosphorus levels under biological nitrogen fixation
ARAúJO, ADELSON PAULO;TEIXEIRA, MARCELO GRANDI;ALMEIDA, DEJAIR LOPES DE;
Pesquisa Agropecuária Brasileira , 2000, DOI: 10.1590/S0100-204X2000000400019
Abstract: the genotypic differences on growth and yield of common bean (phaseolus vulgaris l.) in response to p supply were evaluated in a field experiment under biological n2 fixation. eight cultivars were grown at two levels of applied p (12 and 50 kg ha-1 of p ? p1 and p2 respectively), in randomized block design in factorial arrangement. vegetative biomass was sampled at three ontogenetic stages. the effects of genotype and phosphorus were significant for most traits, but not the genotype ′ phosphorus interaction. the cultivars presented different patterns of biomass production and nutrient accumulation, particularly on root system. at p1, p accumulation persisted after the beginning of pod filling, and p translocation from roots to shoots was lower. the nodule senescence observed after flowering might have reduced n2 fixation during pod filling. the responses of vegetative growth to the higher p supply did not reflect with the same magnitude on yield, which increased only 6% at p2; hence the harvest index was lower at p2. the cultivars with highest yields also presented lower grain p concentrations. a sub-optimal supply of n could have limited the expression of the yield potential of cultivars, reducing the genotypic variability of responses to p levels.
Growth and yield of common bean cultivars at two soil phosphorus levels under biological nitrogen fixation
ARAúJO ADELSON PAULO,TEIXEIRA MARCELO GRANDI,ALMEIDA DEJAIR LOPES DE
Pesquisa Agropecuária Brasileira , 2000,
Abstract: The genotypic differences on growth and yield of common bean (Phaseolus vulgaris L.) in response to P supply were evaluated in a field experiment under biological N2 fixation. Eight cultivars were grown at two levels of applied P (12 and 50 kg ha-1 of P -- P1 and P2 respectively), in randomized block design in factorial arrangement. Vegetative biomass was sampled at three ontogenetic stages. The effects of genotype and phosphorus were significant for most traits, but not the genotype ′ phosphorus interaction. The cultivars presented different patterns of biomass production and nutrient accumulation, particularly on root system. At P1, P accumulation persisted after the beginning of pod filling, and P translocation from roots to shoots was lower. The nodule senescence observed after flowering might have reduced N2 fixation during pod filling. The responses of vegetative growth to the higher P supply did not reflect with the same magnitude on yield, which increased only 6% at P2; hence the harvest index was lower at P2. The cultivars with highest yields also presented lower grain P concentrations. A sub-optimal supply of N could have limited the expression of the yield potential of cultivars, reducing the genotypic variability of responses to P levels.
Yield potential of common bean cultivars in function of phosphorus stress in State of Tocantins  [cached]
Taynar Coelho de Oliveira,Joedna Silva,Sérgio Alves de Sousa,Raphael Campestrini
Journal of Biotechnology and Biodiversity , 2012,
Abstract: This work was developed in order to evaluate the yield potential of 11 common bean cultivars submitted tophosphorus stress. The research was carried in the experimental area of “Universidade Federal do Tocantins –Campus Universitário de Gurupi”. The experimental design was complete randomized blocks with four replications.To represent a stressing environment 20 kg ha-1 of P2O5 was applied at seeding time. The evaluated characteristicswere: plant height, height of first pod insertion, stem diameter, number of pods, number of gains per pod, onehundred gains mass, index of chlorophyll a, b, total and grain yield. It was concluded that the genotypes IPREldoradoand IPR-Colibri presented the better yield potential under phosphorus stress condition. Even underphosphorus stress, most cultivars presented plant height and height of first pod adequate to mechanized croppingsystems.
Evaluation of Common Bean (Phaseolus vulgaris L.) Genotypes for Adaptation to Low Phosphorus  [PDF]
Sixbert Kajumula Mourice,George Muhamba Tryphone
ISRN Agronomy , 2012, DOI: 10.5402/2012/309614
Abstract: Common bean production in Tanzania is constrained by soil phosphorus which is mainly due to inherently low phosphorus content, soil erosion, and fixation by oxides in acidic soils. A study was conducted to evaluate bean genotypes in a screen house pot experiment for their ability to thrive and produce on low phosphorus soil. Assessment of shoot biomass, root biomass, shoot P concentration, P uptake, and yield components was done using three phosphorus levels and seven bean genotypes. Phosphorus levels, namely, control (P0), medium P (40?mg?P/kg), and high P (160?mg?P/kg), were the main plot factor, while the genotypes were the subplot in split plot structure, arranged in a completely randomized design. Shoot and root biomass as well as P uptake increased significantly with increase in phosphorus levels. There was varying response of genotypes in performance in terms of shoot biomass P uptake, and yield in a treatment without P addition. Genotypes MILENIO, BAT477, and A785 were outstanding in terms of root and shoot biomass, P uptake and grain yield under low P treatment. Therefore, those genotypes can be recommended for use in low-phosphorus environment as well as breeding materials. 1. Introduction Bean production in Tanzania is undertaken by small-scale farmers for household consumption, surplus of which is traded for cash. Bean yields are low due to diseases and low soil fertility, particularly phosphorus deficiency [1, 2]. The declining soil phosphorus in Tanzania is due to continued nutrient mining without replenishment. It is estimated that beans remove 12.5?kg?P/ha which is higher than additions in terms of phosphorus fertilisation by resource-poor farmers [3]. It has been reported that soils in major bean growing areas of Tanzania have very low concentrations of extractable phosphorus ranging from 1.6 to 3.1?mg?P/kg soil [4]. The use of fertilizer is very low as it is at an average rate of 1.9?kg?P/ha of cultivated land [5] due to high costs of fertilizers and transport [6], unpredictable rainfall, inadequate supply, untimely availability of fertilizer, and lack of credit [7]. However, phosphorus deficiency can be overcome by corrective soil fertility amendment strategies such as application of phosphatic fertilizers and liming of acidic soils. It is difficult for farmers in developing countries, Tanzania in particular, to undertake soil fertility amendments. Bean production is constrained by low phosphorus; the need for bean varieties are capable of acquiring phosphorus from limiting soil environments is of obvious importance. The ability of
Water and Nitrogen Management Effects on Biomass Accumulation and Partitioning in Two Potato Cultivars  [PDF]
Ashok K. Alva, Helena Ren, Amber D. Moore
American Journal of Plant Sciences (AJPS) , 2012, DOI: 10.4236/ajps.2012.31019
Abstract: Biomass accumulation and partitioning into different plant parts is a dynamic process during the plant growing period, which is influenced by crop management and climate factors. Adequate knowledge of biomass partitioning is important to manage the crops to gain maximum partitioning of assimilates into plant parts of economic significance, i.e. tubers in potato. This study was conducted using two potato cultivars grown in a sandy soil with center pivot irrigation under full irrigation (FI; irrigation to replenish 100% of water loss by evapotranspiration [ET]) and deficit irrigation (DI; replenish only 80% ET) and two nitrogen(N) rates (pre-plant + in-seasonN rates of 56 + 112 or 168 + 336 kg/ha). Plant samples were taken on 22, 44, 66, and 98 days after seedling emergence (DAE). With high N rate, tuber biomass of ‘Umatilla Russet’ cultivar in relation to total plant biomass varied from 23% - 88% and 25% - 86% over 22 to 98 DAE for the FI and DI treatments, respectively. The corresponding partitioning ranges were 30% - 93% and 38% - 93% at the low N rate. With respect to the‘Ranger Russet’ cultivar, biomass partitioning to tubers ranged from 36% - 82% and 23% - 84% for the FI and DI, respectively, at the high N rate, and 29% - 87% and 39% - 95% at the low N rate. Overall, this study demonstrated that within the range of N rate and irrigation treatments the biomass portioning into tubers was largely similar in both cultivars.
The Influence of Water Stress on Biomass and Harvest Index in Three Mung Bean (Vigna radiata (L.) R. Wilczek) Cultivars  [PDF]
Omid Sadeghipour
Asian Journal of Plant Sciences , 2009,
Abstract: The effect of water stress at the vegetative and reproductive growth stages and also no stress conditions on Biomass (B), Harvest Index (HI), Plant Height (PH) and Seed Protein Content (SP) of three mung bean cultivars (Partow, Barymung-2 and vc6368) were investigated. Experiment was conducted at the experimental farm of the Islamic Azad University of Shahre-rey, in Tehran, Iran, during summer 2008. The experiment was set up in a split plot on the basis of complete block design with four replications that placed water stress levels in the main plots and cultivars in sub plots. Correlation coefficients between some traits showed that, Seed Yield (SY) correlated positively with HI (r = 0.829**), B (r = 0.918**) and PH (r = 0.516**). HI correlated positively with B (r = 0.595**). Also, results indicated that the water stress decreased the B, HI and PH, while increased SP in three cultivars. Water stress at the flowering stage was more effective than vegetative stage on B, HI and SP, but less effective on PH. Cultivar partow was less affected, which showed its adaptability to the water stress conditions. Thus, mung bean is most sensitive to the water stress imposes at the flowering stage and in dry regions of Iran can be cultivated the Partow, in addition, for improvement in yield of mung bean, major emphasis should be placed on the B, HI and PH.
Effects of the size of sown seed on growth and yield of common bean cultivars of different seed sizes
Lima, Elvis Rodrigues;Santiago, Aline Silva;Araújo, Adelson Paulo;Teixeira, Marcelo Grandi;
Brazilian Journal of Plant Physiology , 2005, DOI: 10.1590/S1677-04202005000300001
Abstract: a field experiment was conducted to evaluate the effects of planting different sizes of seed of the same cultivar on biomass accumulation and grain yield of common bean (phaseolus vulgaris l.) cultivars of different seed sizes. a 6 x 2 split-plot factorial design with four replicates was employed, with six bean cultivars as main plots and two seed sizes (small and large, the latter twice as heavy as the former) of the same cultivar as subplots. eight weekly samplings of biomass were performed, and yield components were measured at maturity. large seeds increased the leaf area index and the shoot and root biomass of bean cultivars, particularly at the beginning of the growth cycle, but they did not affect the pod biomass. improved growth associated with the large seed was more intense for erect than for prostrate cultivars. plants originating from small seed presented a higher relative growth rate and net assimilation rate than plants from large seed. large seed did not affect grain yield, but reduced the number of seeds per pod, increased the 100-seed mass, and reduced the harvest index. the results indicate that sowing larger seeds of a bean cultivar can improve early-season plant growth, which might be advantageous for crop establishment in stress environments. however, some compensatory effect, associated with delayed leaf senescence, higher net assimilation rate, or greater number of seeds per pod, allows plants originating from small seed to achieve similar grain yield. lack of consistent effects of the seed size on grain yield indicate that the extra costs of sowing only the largest seed would not be profitable, but large seed resulted in larger grains at harvest which usually attain better market price.
Effect of Salicylic Acid and Structurally Related Compounds in the Accumulation of Phytoalexins in Cotyledons of Common Bean (Phaseolus vulgaris L.) Cultivars  [PDF]
Diego Durango,Natalia Pulgarin,Fernando Echeverri,Gustavo Escobar,Winston Qui?ones
Molecules , 2013, DOI: 10.3390/molecules180910609
Abstract: In the present work, isoflavonoid phytoalexin production in response to the application of salicylic acid in cotyledons of four common bean ( Phaseolus vulgaris) cultivars (SA) was evaluated. The time-course and dose-response profiles of the induction process were established by quantifying the isoflavonoids by HPLC. Cotyledons of anthracnose-resistant cultivars induced by SA produced substantially higher phytoalexin contents as compared to the susceptible ones. In addition, maximum levels of phytoalexins (50–100 fold increases) were reached between 96 and 144 h, and when a concentration of SA from 3.62 to 14.50 mM was used. The observations also indicate that there was a relatively good correlation between the phytoalexin contents and the inhibitory effect against C. lindemuthianum; the higher antifungal activity was observed during the first 48 hours for extracts from cotyledons treated with SA at 1.45 and 3.62 mM, and between 96 and 144 h after induction. Finally, compounds structurally related to SA (dihydro-quinazolinones and some imines) showed a strong elicitor effect. Moreover, induced extracts from cotyledons treated with these potential elicitors, besides the properly elicitors, displayed a weak to moderated antifungal activity. These compounds may be considered good candidates for developing of new phytoprotectants. Furthermore, phytoalexin-eliciting substances may contribute for selecting disease resistant cultivars.
Effect of Growth Stage-Based Irrigation Schedules on Biomass Accumulation and Resource Use Efficiency of Wheat Cultivars  [PDF]
Muhammad Mubeen, Ashfaq Ahmad, Tasneem Khaliq, Syeda Refat Sultana, Shahid Hussain, Amjed Ali, Hakoomat Ali, Wajid Nasim
American Journal of Plant Sciences (AJPS) , 2013, DOI: 10.4236/ajps.2013.47175
Abstract:

Climate and weather conditions greatly affect the performance of new wheat cultivars for yield and resource use efficiency. In order to know the effect of irrigation schedules based on growth stage (the most vital criterion in the region) on growth, yield and radiation use efficiency of wheat cultivars in Faisalabad conditions, a study was planned at Agronomic Research Area, University of Agriculture, Faisalabad during 2009-2010. Split plot design with irrigation levels in main plots and cultivars in sub-plots was implied. Irrigation levels were: IT = irrigation at tillering stage, ITS = irrigation at tillering and stem elongation stage, ISB = irrigation at stem elongation and booting stage and ITSBG = irrigation at tillering, stem elongation, booting and grain filling stage. Cultivars selected were: Faisalabad-2008, Lasani-2008, Miraj-2008, Shafaq-2006 and Chakwal-97. Irrigation treatment ITSBG gave higher grain yield (4.23 t·ha-1) followed by ISB (3.60 t·ha-1), however ITSBG was statistically similar to ISB in radiation use efficiency (RUE) for grain yield (RUEGY). Similarly the two treatments were statistically at par in maximum leaf area index, total dry matter (TDM) accumulation, cumulative photosynthetically active radiation (PAR), and RUETDM. Hence where less numbers of irrigations are available, irrigation at stem elongation and booting stage is suitable for achieving economic yield. Lasani-2008 produced maximum grain yield (4.37 t·ha-

Genetics of phosphorus content in common bean seeds
Ribeiro, Nerinéia Dalfollo;Rosa, Simone Saydelles da;Jost, Evandro;Rosa, Daniele Piano;Poersch, Nerison Luís;Maziero, Sandra Maria;
Crop Breeding and Applied Biotechnology , 2011, DOI: 10.1590/S1984-70332011000300007
Abstract: the common bean is an important source of minerals and protein in human nutrition. the objective of this study was to investigate possible maternal effects on phosphorus contents in seeds of the common bean, to estimate the heritability in early hybrid generations for the phosphorus content character and to evaluate the potential for genetic improvement. the controlled crossings were performed among pérola x guapo brilhante and tps nobre x guapo brilhante cultivars. reciprocal f1, and f2 generations as well as backcross populations were produced by each hybrid combination. the range of variation in phosphorus content among tested progenies was from 3.38 to 5.78 g kg-1 dry matter, and no significant maternal effect was discovered. narrow sense heritability was of an intermediate 65.54% to low 21.37 % value. an increase of 19.17 % was obtained for phosphorus content in the seeds using just the three parents tested in this study.
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