Selection of scion/stock combinations of russian plum for intensive cultivation technologies

The basis of modern industrial plantings of Russian plum are intensive technologies with the placement of 1000 to 8000 trees per hectare. For the formation of such agrocenoses, seedlings of varieties grafted on adaptive, weak-growing clonal rootstocks are used, which are more effective in comparison with vigorous seed seedlings. Today, one of the important tasks of modern horticulture is to improve the assortment, increase its adaptability based on the selection of compatible clonal rootstocks of different growth strengths of local breeding and the selection of the most productive scion/stock combinations. Of relevance to the southern zone of fruit growing, the question of using scion/stock combinations of the intensive type, combining complex resistance to biotic and abiotic stresses, giving stable high yield of trees, good taste and canning qualities of the fruits and their transportability, as well as being resistant to diseases and pests. The work, сonducted on Krymsk Experimental Breeding Ststion –VIR Branch (Krymsk, Krasnodar Territory), presents the results of studies evaluating the economically valuable traits of varieties and rootstocks of Russian plum. It was established that grafted trees of the Globus and Kubanskaya Cometa varieties on a medium-sized clonal rootstock Kuban 86 with a planting pattern (5.0×3.0 m) over the years of research exceeded the control and plant tested clonal rootstocks (average yield 24.3 kg per tree, and 23.5, and the average mass of the fruit 51.5 and 37.2 g). On the dwarf rootstock (5.0×1.5 m), the best scion/ stock combinations were the combinations Globus/VVA 1 and Kubanskaya Cometa/VVA 1. Based on biological and economic estimates for the complex of economically valuable traits, the most valuable plum rootstocks and rootstocks were identified Russian. Practical recommendations are given to manufacturers to create effective plum gardens in this area.

The Optimum Plant Density for Vigorous Seed Production in Safflower

Seed viability and vigor have been influenced by several factors including soil and climatic conditions, plant nutrition, fertilization, irrigation, plant population and post-harvest storages. The study was conducted to determine the appropriate plant density for vigorous seed production in safflower. The effects of row spacing (14 and 28 cm) and seeding rate (40, 80, 120, 160 and 200 seeds m-2) on yield, yield components and seed quality of safflower were detected in the study. The results showed that increased seeding rates resulted in enhanced seed yield and the highest seed yield was obtained from 14 cm and 200 seed m-2 with 3320 kg ha-1. The row spacing and seeding rate did not cause a significant difference in oil and protein contents. Laboratory emergence, germination after accelerated ageing (AA) and electrical conductivity tests were suitable for determining seed quality among the seed lots, while standard germination, cool and cold tests were not appropriate. The highest laboratory emergence percentage and germination after AA were determined in 80 seed m-2 but field emergence percentage in 120 seed m-2. It was concluded that the 14 cm row spacing and seeding rate of 120 seed m-2 should be advised for high yielding seed production regardless of seed vigor in safflower.

Field Performance of Differentially Deteriorated Seed Lots of Maize (Zea mays) under Different Irrigation Treatments

A sub-sample of maize (cv. KSC301) seeds was kept as control or vigorous seed lot and two other sub-samples with about 16% moisture content were artificially deteriorated at 40C for 16 and 18 days. The three seed lots had seed viabilities of 99% (V1), 91% (V2) and 79% (V3). Laboratory tests were carried out as CR design with four replicates. However, the field experiment was conducted as factorial based on RCB design with three replicates to investigate the performance of differentially deteriorated seed lots under four irrigation treatments (irrigation after 70, 90, 110 and 130 mm evaporation from class A pan). Germination and emergence times significantly increased with increasing seed deterioration, but mean viability percentage, seedling dry weight, seedling emergence and protein and grain yields decreased as seed deterioration increased. Even plants from less deteriorated seed lot (V2) with acceptable germination (91%) showed 25.1% reduction in grain yield per unit area. The superiority of V1 to V2 seeds of maize increased as water limitation increased. Protein yield was also decreased as a result of seed deterioration. Seedling dry weight highly correlated with the field emergence and grain and protein yields. Thus, it is necessary to produce and cultivate high vigor seeds of maize, in order to ensure satisfactory yield achievement, particularly under adverse environmental conditions.

Assessment of the physiological potential of bell pepper seeds and relationship with seedling emergence

The objective in this study was to verify the efficiency of different procedures for evaluating the physiological potential of bell pepper seed and identify its relationship with germination at different temperatures and with seedling emergence. Five seed lots each of the Reinger and Sentinel hybrids were used. Seed physiological potential was evaluated by germination, saturated salt accelerated aging (48 h/41 °C), seedling emergence (percentage and speed), and tetrazolium tests (preconditioning at 45 °C/3 h and seed staining at 45 °C/2 h). Germination (percentage and speed) on a thermogradient table at 15 °C, 18 °C, 21 °C, 25 °C and 30 °C was also evaluated the saturated salt accelerated aging and tetrazolium tests are suitable for access the physiological potential of bell pepper seeds. It was also confirmed that vigorous seed lots perform better when exposed to different temperatures during germination.

Isozyme polymorphism to detect genetic diversity of Jatropha curcas (L.) in India

The Indian Government identified Jatropha curcas L. as the most suitable treeborne oilseed for the production of bio-diesel. The species has spread to many parts of India due to its ability to withstand adverse conditions. Breeding of inter and intra specific Jatrophas for the exploitation of hybrid vigour is one of the most economical means of tree improvement. To study the genetic base of the species distributed in India, 55 accessions of J. curcas from Jammu to Kanyakumari and Jodhpur to Kolkata were assessed using isozyme markers. Fifteen enzyme systems were evaluated for their efficacy in distinguishing the accessions. While three (formate dehydrogenase, malate dehydrogenase and peroxidase) were found useful, twelve did not exhibit any variation and had fixed monomorphic alleles. Each polymorphic enzyme system produced one well resolved polymorphic region except peroxidase which had three. On an average 4 loci (26.67%) were found to be polymorphic (P) and mean observed number of alleles per locus (A) was 1.533. Average observed heterozygosity (Ho) was 0.1082 and expected value (He) was 0.0993 with and gene flow Nm = 0.2177 showing low level of genetic variation among different accessions suggesting poor segregation of genes over generations. The isozyme variation was measured by standard gene diversity measures using POPGENE v. 1.32. Dendrograms revealed very low heterozygosity leaving little scope for exploitation of hybrid vigour and suggesting that initiating breeding programmes with Indian land races may not lead to substantial genetic gain, vigorous seed set and higher volumes of oil yield.

Effects of Safener CGA-154281 on Metolachlor/Atrazine Injury to Corn (Zea mays)

Three seed lots each of two varieties of field corn were compared in greenhouse and field studies. Cold test germination percentages of the seed lots were as follows: 79, 85, and 93% for ‘DK656’; 77, 84, and 91% for ‘T1100’. Tank mixes of metolachlor or metolachlor with safener CGA-154281 plus atrazine or formulated metolachlor/atrazine with and without the safener were applied preemergence. Crop stand of either variety or among seed lots within a variety was not affected by herbicide treatments. In the greenhouse, fewer corn plants were injured and growth of plants was greater with herbicides with safener than herbicides without safener. Plant heights and weights at harvest from the most vigorous seed lot of DK656 were higher than those of the other two seed lots. Herbicide treatments with the safener did not cause significant injury to corn in the field. Yields of both varieties increased with herbicide treatments in one conventional planting. No significant differences in injury or yields occurred among seed lots within varieties.

FEATURES OF GROWTH AND FRUITING APPLE VARIETIES IN GARDEN OF INTENSIVE TYPE

The research was carried out at the sites of production study of VNIISPK in the period from 1990 to 2016. The plots were located on gray and dark gray forest soils of medium-loamy mechanical composition with the capacity of the humus horizon of 30-50 cm. The climate is temperate-continental with the vegetation period of 175-185 days. Average annual air temperature is 4.6⁰C, minimal temperature in winter is -40⁰C, maximal temperature in summer is +38⁰C. The study was conducted in accordance with generally accepted methods of variety investigation and frost resistance study in the laboratory using a freezer “ESPEC” PSL-2 KPN. The possibility of obtaining low-sized apple trees on the roots of vigorous seed rootstocks with the intercalary inserts of a low-sized clone rootstock was established. The insertion components of a low-sized clone rootstock provided the significant weakening of tree growth and precocity in comparison with a vigorous seed rootstock. High precocity was revealed in Orlovim, Ranneye Aloye, Zhelannoye and Yubilar (on the level of Papirovka). Imrus and Orlik showed high specific load per unit of cross-sectional area of the trunk (2.0). Annual or non-sharp periodical fructification in those varieties were developed at the expense of flower bud laying on the growth of fruit bags of twigs in the year of fruiting with good foliage, and the alternation of fruiting of some branches and trees. The best variety-rootstock combinations were revealed: summer varieties Zhelannoye/3-3-72, Orlovim/3-3-72, Ranneye Aloye/3-3-72 and winter varieties Imrus/3-3-72 and Orlik/3-3-72.