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Salinity is one of the main factors that causes losses in crops up to 50%, which puts world food security at risk. During evolution, plants have acquired defense mechanisms, which are regulated by specific genes whose main function is to counteract damage by salinity. Genetic variability in crops is necessary for stress-tolerant genotypes to occur. One of the strategies that can be used to find tolerance is the combination of mutagenesis and plant tissue culture, since thousands of plants are produced in confined spaces and short periods; in addition, with the use of selective agents such as NaCl plants can be obtained tolerant to salinity. This review will address topics related to plant tissue culture, induced mutagenesis and the combination of both as strategies to obtain salinity tolerant plants of agricultural interest. [ABSTRACT FROM AUTHOR]

To develop an in vitro selection protocol, it is necessary to differentiate between tolerant and susceptible cultivars to the studied factor. The present work was carried out with the objective of selecting the temperature that allows to in vitro differentiating the response of the Phaseolus vulgaris cultivars 'ICA Pijao' (susceptible) and 'Tío Canela-75' (tolerant) to high temperatures. Different temperatures (30, 35, 40, 45 and 50 °C) were applied to seeds of the two cultivars. In vitro seed germination percentage, radicle and plumule length, number of explants that formed callus and number of shoots per callus were evaluated. It was possible to differentiate between cv. 'ICA Pijao' (susceptible) and 'Tío Canela-75' (tolerant) with the variables radicle length, plumule length, percentage of calli formed and number of regenerated shoots. It was selected 35 °C as the selective agent. [ABSTRACT FROM AUTHOR]

The common bean (Phaseolus vulgaris L.) production is limited by biotic and abiotic factors. Among them, water stress, saline or high temperatures. To solve this problem, genetic improvement programs are aimed at the search for tolerant cultivars. The objective of this work was to determine the effect of heat treatment at high temperatures on the in vitro germination of P. vulgaris cv. 'ICA Pijao'. For this, seeds of 1-4 months of harvest were used. It were treated at 35 ± 2 °C in an incubator or immersed in water in a thermal bath. As a control, seeds at room temperature (28 ± 2 °C) were used. The results showed that in vitro germination was not less than 90%, however the two heat treatment conditions affected the length and thickness of the radicle and the length of the plumule. Considering the results, the ease of application and the non-affectation of germination, it is recommended to use the heat treatment at 35 ± 2 ºC in an incubator. This could be used to induce high temperature stress in the common beans cv. 'ICA Pijao' in an in vitro selection protocol. [ABSTRACT FROM AUTHOR]

The common bean (Phaseolus vulgaris L.) production has been very important in Cuba, however, several factors affect the yield of this crop and not all cultivars of beans respond the same way to the stressful conditions. The aim of this study was to determine the effect of water deficit induced by PEG 6000 on the cultivar 'ICA Pijao'. The results showed that increasing concentrations of PEG 6000, reduced the percentage of P. vulgaris cv. ICA Pijao in vitro germination, which confirmed that this stressor agent could be useful to elucidate the physiological response and concentrations PEG 6000 to be used in bioassays to evaluate the plant response in this cultivar should be less than 18 %. [ABSTRACT FROM AUTHOR]

The black spot cactus is caused by Pseudocercospora opuntiae a disease spread among production systems. The process of pathogenesis, comprising an incubation period of 90 d. and the development of symptoms can occur in 25 d.; however, is still limited information pathosystem P. opuntiae in Opuntia sps. This study aimed to evaluate the effect of extracellular products and spores of P. opuntiae on cactus pear under in vitro conditions. Three genotypes from zygotic embryos and two genotypes product of field selection which were characterized as tolerant (T) and resistant (R) to P. opuntiae were evaluated. Opuntia in vitro seedlings were inoculated with the extracellular extract and a suspension of 108 conidia m/l, the damage at 15, 30,45 and 60 d. post-inoculation (dpi) were evaluated. After 60 dpi symptoms occurred in explants inoculated with pure fungus, while the excretion products of the fungus in liquid medium showed ability to induce symptoms similar to fungal inoculum. These results demonstrate that P. opuntiae infected Opuntia explants under in vitro culture conditions, which could be an important tool in the selection of resistant genotypes to black spot in Opuntia sps. [ABSTRACT FROM AUTHOR]

Yam tuber production has been affected for anthracnose, decreasing farmers' incomes. Genetic resistance has been attempted; however, the species narrow genetic base favors fungal re-infection. Selection of new cultivars is hampered by low flowering and seed setting. The ability of embryogenic cultures to generate in vitro resistance to Colletotrichum gloeosporioides by co-culturing proembryogenic masses (PEMs) with several concentrations of the fungal filtrate was evaluated. PEMs were induced from "Pico de botella" var. foliar explants on MS supplied with 2,4-D. Proliferated PEMs were challenged with several concentrations of the culture filtrate and dually cultured with fungal mycelia. PEMs showed susceptibility to fungal filtrate and mycelia. No embryos were recovered from challenged or filtrate-free PEMs. [ABSTRACT FROM AUTHOR]

Growth in a PDA medium of six isolates of A. solani, coming from the microbial cultivation collection of IBP, and the phytotoxicity of the culture filtrate of each one were studied to evaluate the influence of isolates on the culture filtrate phytotoxity of A. solani. Results showed that the six isolates were phytotoxic on potato plantlets var. Desireé. However, significant differences were observed in the degree of affectation caused by culture filtrates of each isolate on plants of this genotype. These results confirmed the influence of isolate in the production of culture filtrates of A. solani. Isolate CCIBP-Vas4 was selected based on the results, since it caused the highest degrees of affectation. Besides, no correspondence among isolates in vitro growth and phytotoxicity of culture filtrates on potato plantlets var. 'Desirée' were found. [ABSTRACT FROM AUTHOR]