Shoot initiation for Macadamia integrifolia explant with tissue culture technique

Macadamia nuts are grown in subtropical and tropical regions and endemic species in Greenland that can be commercially developed in Indonesia. Macadamia’s generative propagation tends to have problems in its seed stock. It often experiences obstacles in field seed stock, and the production requires a long time because it has a thick shell (pericarp). Macadamia initiation needs technology to prevent extinction. One of the propagation is through the technique culture in vitro. This research was conducted to determine the initial response of basic media and to know the response of Macadamia growth in vitro. This research used five media which are Media 1 (DKW with BAP 0.1 ppm, kinetin 0.1ppm), Media 2 (WPM with BAP 1 ppm), media 3 (DKW), media 4 (MS), media 5 (MS with BAP 0.5 ppm). The results showed that media 1 and 3 (DKW media) had a good response for leaf and shoot growth in macadamia explants.

Comparative study of apple plantations on seed and clonal stocks in the steppe zone of the Southern Urals

In recent years, Russian gardeners have become interested in apple seed stocks, since they are indispensable for growing planting material of the highest quality categories for the purpose of setting up mother-cuttings, nurseries of clonal stocks and intensive orchards intended for obtaining organic products. The advantage of apple seed stocks is not only in a powerful root system and resistance to biotic and abiotic stressors, but also in the absence of a harmful viral infection from which almost all clonal stocks in Russia suffer. The opinion that trees are more vigorous on seed stocks, and orchards later enter in the fruiting period is erroneous, since there are developed technologies that make it possible the establishment of intensive apple tree plantations that enter the fruiting period 2 years after grafting. Among the apple clonal stocks, the intensively propagated form 54-118 is characterized by good anchoring and winter hardiness. Due to the lack of scientific data on the comparative study of seed and clonal stocks in the context of scion/stock combinations, we have begun a long-term study in order to identify the most promising of them in terms of early fruitfulness and high productivity. Long-term studies were carried out on the basis of the Orenburg branch of the Federal Horticultural Research Center for Breeding, Agrotechnology and Nursery from 2000 to 2020. The analysis of the results of the tests carried out shows that all the plantings on stocks 54-118 and 64-143 turned out to be early fruitfulness, and the stocks were suitable for intensive gardening, since the varieties grafted on them have a restrained growth force and a compact crown. The smallest height from 1.9 to 2.8 m was noted in trees on the 54-118 stock, on the 64-143 stock this parameter, depending on the variety, varied from 3.2 to 3.8 m. The largest crown diameter (over 3.0 m) and the largest projection area of the crown had plantings of all varieties on the seed stock of Purple Ranetka. The yield of apple tree plantations on stock 54-118 varied from 10.4 (Serebryanoe Kopitce variety) to 14.1 t/ha (Chudnoe variety), and revenue from the sale of products from 1 ha ranged from 263.1 to 356.7 thousand rubles. The highest profitability on clonal stock 54-118 was distinguished by perennial plantations of the Chudnoe variety (83.8 %). On stock 64-143, the yield of plantings varied from 10.2 t / ha (Serebryanoe Kopitce variety) to 13.5 t / ha (Chudnoe variety), the proceeds from the sale of products per hectare also varied from 258.1 thousand rubles. up to 341.5 thousand rubles. The highest profitability of production was noted in the plantations on the stock 64-143 of the variety Mechtatelnitsa (82.2 %). The average yield of apple varieties grafted on the seed stock of Purple Ranetka ranged from 8.2 (variety Letnee Polosatoe (K) to 9.3 t / ha (variety Serebryanoe Kopitce); high profitability of production was distinguished by plantings of the variety Mechtatelnitsa on ranetka purpurovaya (16.3 %).

ADAPTIVE ABILITIES OF CHERRY OF TURGENEVKA VARIETY IN THE CONDITIONS OF EXTREME CONTINENTAL CLIMATE OF THE ASTRAKHAN REGION

The article presents results of the first stage of the study of the introduced Turgenevka cherry variety on stocks of different growth rates under the conditions of extreme continental climate of the Northern Caspian region to substantiate its use in intensive planting of the arid zone. The aim of our research is to study the economic and biological characteristics and adaptability of Turgenevka variety to the abiotic stress factors of the winter period, which appear on the territory of the Astrakhan region. The study was carried out at the experimental field of the Caspian Agrarian Federal Scientific Center of the Russian Academy of Sciences. The records and observations were carried out in 2017-2020, in triple replication. The experiment plot was laid down in 2017. The research material is the introduced Turgenevka cherry variety. As a result of the research, the influence of stocks on periods of the main phenological phases, biometric parameters of trees, productivity, early maturity and quality of cherry fruits was revealed. At the initial stage of plant growth and development, it was found that clonal stocks slightly accelerate the start of growth and flowering of the grafted trees in comparison with the trees on seed stock. Turgenevka variety is characterized by a more restrained tree growth (1.5 m ) on a well-grown seed stock (mahaleb cherry). Mahaleb cherry stock also has a positive effect on early maturity of the variety. The largest fruits, 5.7 g, were formed on VTs-13 stock. The tasting score of the fruit was 4.5 points. A complex assessment of the variety resistance to diseases and pests was carried out. The influence of the stock on chemical fruit composition was not revealed. Turgenevka variety showed good resistance to unfavorable environmental factors.

TECHNOLOGY OF PLANT RAW MATERIALS MICROBIOLOGICAL PROCESSING WITH PLEUROTUS STRAINS FOR FEED PRODUCTS PRODUCTION

A technology for pilot production of feed products via microbiological conversion of plant raw materials (mixed substrate of pine sawdust and vegetative part of Jerusalem artichoke) by Plerotus ostreatus PO-4.1 and Pleurotus djamor PD-3.2 strains is developed. The technology includes hydrodynamic activation of substrate at the seed stock production stage. The overall technology includes three key stages: submerged fermentation of pure cultures of production strains; submerged-solid phase fermentation of hydrodynamicly activated plant raw materials for seed stock production; solid-state fermentation of mechanically ground plant substrate for feed products production. A successful approbation of submerged-solid state fermentation of production strains on media containing 3% of hydrodynamicly activated raw materials allowed for obtaining seed stock with 14.5 g/l yield of submerged mycelium biomass fully adopted for this type of substrate. Further use of this seed stock biomass at the solid state fermentation stage makes the overall process duration three times shorter compared to existing technologies for direct wood waste bioconversion. The pilot plant results show valuable practicability of plant raw material hydrodynamic activation with the purpose of enhancing its bioaccessibility with consequent increase in degree of microbiological conversion. The product of bioconversion contains 14–16% of protein, biofiber, vitamins and minerals and could be considered for successful use as feed by agricultural enterprises.

Selection of seed stocks for propagation of apple trees in the Far East

The article presents the results of research on the selection of seed stocks aimed at the development of intensive horticulture in the Far Eastern region, which has great potential for growing apple fruits. There were summarized materials on the study of seed stocks of apple trees. In modern conditions in fruit growing, the most relevant direction is the creation of high-yielding apple varieties with high adaptive properties. Varieties must be early-growing, have high immunity and resistance to the most harmful pathogenic, and also have good compatibility with seed stocks that are resistant to the abiotic and biotic environmental factors of the Far Eastern region. The use of seed stocks makes it possible to propagate seedlings of the most promising varieties free from harmful viral infections without losing their genetic stability. Plantings planted with such planting material do not need expensive supports and require significantly fewer mineral fertilizers and water, because they have a powerful root system that penetrates into the deeper layers the soil. Seed stocks of the apple tree are initially free from viral infection, and, unlike the clonal stocks, do not require expensive recovery, which leads to significant material savings. High grafting on seed stock not only contributes to the accelerated entry of gardens into the productive period, but also helps protect trees from damage from sunburn and frost. The production and biological study of the seed stocks of the apple tree was carried out in the form of a collection variety study and production variety testing. The field method is used to evaluate seed stocks. The developed and scientifically substantiated methods for planting apple orchards on seed stocks make it possible to create stands that are resistant to the climate of the Far Eastern region and stably produce marketable fruits for several years. It was revealed that the Siberian berry apple tree, and the variety Ranetka Yantarnaya are the most highly adapted and can be used as a seed stock.

Production of asari (Manila) clams, Ruditapes philippinarum, during the period of harvest decrease in the 2000s in the Banzu tidal area, Tokyo Bay

In Tokyo Bay, the harvestable quantity of asari (Manila) clams Ruditapes philippinarum has been decreasing since the late 1990s. We conducted a field investigation on clam density in the Banzu culture area from April 1988 to December 2014 and collected records spanning January 1986 to September 2017 from relevant fisheries cooperative associations to clarify the relationship between the temporal variation in stock abundance and the production activities of fishermen. The yearly variation in clam abundance over the study period was marked by larger decreases in the numbers of larger clams. A large quantity of juvenile clams, beyond the biological productivity of the culture area, may have been introduced as seed stock in the late 1980s despite the high level of harvestable stock. The declines in harvested quantity began in the late 1990s and may have been caused by decreases in harvestable stock despite the continuous addition of seed stock clams. The harvested quantity is likely to be significantly dependent upon the wild clam population, even within the culture area, as the harvestable quantity was not correlated with the quantity of seed stock introduced during the study period. These declines in harvested quantity may have resulted from a decreasing number of operating harvesters due to the low level of harvestable stock and consequently reduced profitability. Two findings were emphasized. A certain management style, based on predictions of the contributions of wild and introduced clams to future stock biomass, is essential for economically-feasible culturing. In areas with less harvestable stock, actions should be taken to maintain the incomes of harvesters while avoiding overexploitation, even if the total harvest quantity decreases.

Herbicide-tolerant endophytic bacteria of rice plants as the biopriming agents for fertility recovery and disease suppression of unhealthy rice seeds

Background Dirty panicle disease (DPD) caused by several fungal phytopathogens results in damage and depreciation of rice seeds. Unhealthy rice seeds with DPD are potent reservoirs of pathogens and unable to be used as seed stock as they can spread the disease in the paddy fields leading to the severe loss of rice yield and quality. In this study, we aim to search for beneficial endophytes of commercially cultivated rice plants and utilize them as biostimulants in seed biopriming for fertility recovery and disease suppression of unhealthy rice seeds. Results Forty-three bacterial endophytes were isolated from rice plants grown in the herbicide-treated paddy fields. Five isolates of these endophytes belonging to the genus Bacillus show excellent antifungal activity against fungal pathogens of DPD. Based on germination tests, biopriming unhealthy rice seeds by soaking in bacterial suspensions for 9 or 12 h was optimal as evidenced by the lowest disease incidence and longer shoot and root lengths of seedlings germinated, compared with controls made of non-treated or hydroprimed healthy and unhealthy seeds. Pot experiments were carried out to evaluate the impact of seed biopriming, in which the percentage of healthy rice yield produced by rice plants emerging from bioprimed seeds was not significantly different, compared to the controls originating respectively from non-treated healthy seeds and chemical fungicide-treated unhealthy seeds. Conclusion Biopriming of unhealthy rice seeds with herbicide-tolerant endophytic bacteria could recover seed fertility and protect the full life cycle of emerging rice plants from fungal pests. With our findings, seed biopriming is a straightforward approach that farmers can apply to recover unhealthy rice seed stock, which enables them to reduce the cost and use of agrochemicals in the commercial production of rice and to promote green technology in sustainable agriculture.