The effects of inoculation and N fertilization on soybean [Glycine max (L.) Merrill] seed yield and protein concentration under drought stress

  1. Basal, A. Szabó

 

Institute of Crop Sciences, Faculty of Agricultural and Food Sciences and Environmental management, Böszörményi út 138, Debrecen, Hungary

 

DOI: 10.15547/ast.2018.03.044

(Manuscript received 7 June 2018; accepted for publication 8 August 2018)

 

Abstract. An experiment was conducted during 2017 growing season in Debrecen, Hungary to investigate the effects of inoculation and N fertilization on the seed yield and protein concentration of soybean [Glycine max (L.) Merr.] cultivar (Boglár) under three irrigation regimes: severe drought (SD), moderate drought (MD) and control with no drought stress (ND). Three N fertilizer rates were applied: no N (0N), 35 kg/ha (35N) and 105 kg/ha of N fertilizer (105N). Half of the seeds in each treatment were inoculated with Bradyrhizobium japonicum inoculant. The results showed significant differences in the seed yield associated with both inoculation and irrigation, whereas there were no significant differences in the seed yield associated with fertilization. When seeds were inoculated, yield was increased when (35N) was applied compared to (0N); however, high rate (105N) reduced the yield to a level even less than (0N). When seeds were not inoculated, the highest rate of N increased the yield the most compared to the other two N fertilizer rates under drought. Under severe drought, inoculation was positively and significantly correlated with yield; however, adding N fertilizer increased the yield of non-inoculated plants compared to the inoculated ones, regardless of N-fertilizer rate. Protein concentration in the seeds was significantly affected by irrigation and by fertilization, but not by inoculation. Protein concentration increased as N fertilization rate increased, regardless of inoculation or irrigation; moreover, increasing N rate reduced the correlation coefficient of protein concentration with irrigation. It was concluded that adding N-fertilizer is not always recommended, especially when seeds are inoculated before being sown; however, it is very important under severe drought stress to sustain yield. Enhanced protein concentrations could be achieved by applying N fertilization, whether the seeds were pre-inoculated or not.

 

Yield and seed quality of some soybean (Glycine max. L) varieties, cultivated in Osmaniye region, Turkey

F.F. Aşik, R. Yildiz

 

Oil Seeds Research Institute, 80950 Osmaniye, Turkey

 

DOI: 10.15547/ast.2018.03.042

(Manuscript received 21 May 2018; accepted for publication 2 August 2018)

 

Abstract. This study was carried out to determine yield and seed quality of 14 soybean varieties (Blaze, Ataem-7, Bravo, İlksoy, Çetinbey, Nova, Atakişi, Cinsoy, Adasoy, Umut-2002, Türksoy, Arısoy, HA.16-21 and SA-88), conducted with 3 replicates, according to the Randomized Block Experimental Design in the Osmaniye region, Turkey during 2016 growing season. Plant height, seed number per pod, first pod height, number of branches per plant, number of pods per node, number of pods per plant, harvest index, protein content, oil content, hundred seed weight, seed yield and fatty acid composition were the parameters examined. It was found that the controlled parameters values at different soybean varieties ranged as follows: plant height – between 69.47cm (Blaze) and 101.83cm (HA.16-21); number of seeds per pod – between 1.82 units/pod (Adasoy) and 2.21 units/pod (Blaze); first pod height – between 13.10cm (Blaze) and 22.53 cm (Umut-2002); number of branches per plant – between 1.07 units/plant (HA.16-21) and 3.00 units/plant (Nova); number of pods per node – between 2.43 units/node (Umut-2002) and 4.81 units/node (Adasoy); number of pods per plant – between 27.40 units/plant (Umut-2002) and 47.73 units/plant (Adasoy); Harvest Index values – between 43.99% (HA.16-21) and 54.72% (Ataem) – 55.42% (Blaze); protein content – between 36.09% (Nova) and 39.17% (Çetinbey); oil content – between 15.71% (Blaze) and 19.73% (Türksoy) – 19.82% (Arısoy); 100 seed weight – between 12.54g (Arısoy) and 19.18g (Çetinbey); seed yield – between 2470.41 kg/ha (Arısoy) and 3280.03 kg/ha (Adasoy); acid composition values: palmitic acid – from 9.97% (Türksoy) to 11.47% (Çetinbey); stearic acid – from 3.82% (Ataem-7) to 4.38% (Türksoy); oleic acid – from 22.39% (Bravo) to 28.14% (Çetinbey); linoleic acid – from 47.30% (Çetinbey) to 53.26%  (Ataem-7) and linolenic acid – from 5.49% (Türksoy) to 6.88% (Bravo). The soybean varieties tested showed different advantages over the individual parameters: in terms of seed yield – Adasoy (3280.03 kg/ha) and Atakişi (3260.60 kg/ha) varieties; in terms of protein content – Çetinbey (39.17%) followed by SA-88 (38.55%) genotype; in terms of oil content – Türksoy variety (19.82%) followed by Arisoy (19.73%) variety; in terms of fatty acid composition the results are very diverse.

 

Study of the effect of soil trampling on the structural elements of yield and productivity of soybean

V. Sabev, S. Raykov, V. Arnaudov
Abstract. The study was conducted in the experimental field of the Institute of Forage Crops Pleven, Pavlikeni branch during the 2005–2007 period. The objective of the study was to determine the effect of soil trampling by the wheels of the tractor unit on the structural elements of yield and productivity of soybean. It was found that soil trampling by the tractor unit tires had a negative effect on the ramification number, being most pronounced after three and four passages. The trampling influenced negatively also the pod number and grain yield per plant, the results being statistically significant. The single and two-fold passage decreased productivity 13 to 24% and after three and four passages over the area the yield was reduced to 40% and the yield was lower at very good statistical significance.
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