-Seven traits related to flowering and sex expression in melon were studied and their reaction to application of two growth regulators (ethrel and gibberellic acid) was observed. Four monoecious genotypes (Sesame, Pobeditel) and four andromonoecious genotypes (Chinese muskmelon, Anannas, Fiata,

This study examined the influence of agroecological conditions on the ontogenesis and production yield traits of black oat (Avena strigosa Schreb.). Understanding the agronomic and phenological properties related to productive properties of black oats can enable more successful introduction into new areas of oat cultivation. Field microexperiments were performed during the three consecutive years (2017–2019) on the two localities in South Banat, in Serbia, which differed in soil type: carbonate chernozem and humogley, respectively. The results showed that all investigated traits of oat in the chernozem soil type were higher when compared with measured traits obtained from the humogley soil type. The average value of yields of aboveground biomass, yield and protein content were significantly higher in relation to the humogley, by 13%, 17% and 11%, respectively for all three seasons. Observed by years, all productivity parameters differed significantly, which confirmed that the productivity of the cultivated plants was strongly influenced by different agroecological, soil and climatic conditions in Pannonian environments. The aboveground biomass and grain yield obtained from the humogley soil type indicate that this species can be successfully grown and utilized in production as a cover or fodder crop even in less favorable soil conditions.

Phosphate solubilizing bacteria (PCB) is a group of heterotrophic bacteria capable of solubilizing organic and inorganic phosphorus from insoluble compounds, releasing phosphate available for plant uptake. In this study endophytic bacteria were isolated form nodules of French bean grown in different intercropping systems. Only 14 out of 158 endophytic isolates were able to solubilize tricalcium phosphate (TCP). None of them were observed to solubilize FePO 4 and AlPO 4. Eight isolates formed solubilization zones larger than 3 mm and were used for further test. The TCP solubilization was measured in liquid Pikovskaya medium and ranged from 14-182 μgml-1 of soluble phosphorus. TCP solubilization was correlated with acidity and pH decreasing from 7.4 to 5.57 and 4.91 for the lowest and the highest solubilizer, respectively, were observed. The most efficient isolate MP18 was selected and identified as Pseudomonas sp. according to 16S rRNA gene analysis.

This research was conducted with the aim to among forty-one tested tomato (Lycopersicon esculentum Mill) populations distinguish those tolerant to limited water supply. Tolerance assessments were performed by using sixteen drought stress selection indices calculated on the basis of tomato shoot and root dry weight yields determined at water stress and non-stress conditions. Populations were differentiated in groups using the method of cluster analysis. The pot experiment was set in controlled greenhouse conditions and comprised optimally irrigated control and drought treatment (35.0 and 20.9% volumetric soil water content, respectively), imposed at the phase of intensive vegetative growth. The experiment was conducted at the Institute for Vegetable Crops in Smederevska Palanka, Serbia. The analyzed tomatoes exhibited significant differences in terms of response to limited irrigation, which had more pronounced effect on shoot dry weight than on the roots (average decrease of 64.4 and 35.7%, respectively). Consequently, root fraction in the total dry weight increased at drought for 68.2% on average. Shoot and root dry weights were positively correlated at optimal irrigation but not in drought, implying genotypic differences in terms of root adjustments to stress conditions. As for the calculated selection indices, substantial variation was found among the populations enabling their ranking in terms of drought tolerance. Since ranking was not the same in all cases, clustering the populations was performed taking into account all sixteen selection indices. The results of this analysis indicate that populations designated with numbers 126, 124, 131, 125, 128, 105, 101, 138, 110, 132 and 109 in Institute for Vegetable Crops germplasm collection exhibit satisfactory level of drought tolerance at vegetative phase and therefore may be used as parents in breeding programs. [Projekat Ministarstva nauke Republike Srbije, br. TR 31005 i br. TR 31059]

This study was aimed to assess drought tolerance in twelve tomato populations collected in the territory of Serbia and to investigate relationships and repeatability among sixteen drought tolerance indices. Drought tolerance was estimated at the stage of intensive vegetative growth, on the basis of dry weight yield determined at optimal and limited irrigation (volumetric soil water content of 35.0 and 20.9%, respectively). The trial was set in pots placed in the greenhouse. Significant differences were found among populations in terms of all considered parameters; populations G125, G105 and G104 performed well in both irrigation regimes. High repeatability was found between the selection indices TOL and SSPI, STI and GMP, DWdr and YI, and among SI, SSI, RDI, SDI and RD. Principal component analysis allows simultaneous evaluation of populations and interpretation of interrelationships among the indices; it may be recommended as a method of choice for data analysis in further studies on drought tolerance in tomato.