Culturing of plant cells, tissues and organs in controlled and disinfected conditions which includes light intensity, humidity and temperature is known as “Plant Tissue Culture”. From the past several years, regeneration of different plants under lab conditions from different plant cells and tissues has been playing a very important role in examining plant genetics and their physiology. This technique is known to help the plants in propagation and increases their soil’s agronomic performance. In this review, we focus on the impact of plant tissue culture techniques in wheat crop, such as embryo culture, mature and immature embryo culture, effect of media on callus induction and regeneration, media and genotype interaction on callus induction and regeneration, somatic embryogenesis, correlation of agronomic trait on callus induction, and regeneration and somaclonal variations.

Cucurbita moschata is a plant which belongs to Cucurbitaceae family and it is widely used in traditional medicine. As there is lack of information available on the tissue culture and secondary metabolites of Cucurbita moschata, plant tissue culture appears to be a viable option for the improvement of the Cucurbita species by means of plant tissue. The establishment of an efficient in vitro plant regeneration system suitable for genetic transformation is the key step in this approach. Plant growth regulators hold great potential for their effect and impact on callus development and regeneration in Cucurbita moschata. Callus formation and regeneration in plants is not only effected by PGRs but also dependent upon the moisture content, light intensity, temperature and type of explant. Present study highlighted the medicinal importance of Cucurbita moschata secondary metabolites production. The tissues having higher rates of cell division produce growth regulatory substances including cytokinins, auxins and many other secondary metabolites. Secondary metabolites regeneration and effectiveness in tissue culture is generally a quantifiable trait that repeatedly varies between plant species and within a plant species among, varieties, subspecies cultivars and ecotypes. So tissue culture regeneration of secondary metabolites can become variable particularly when many metabolic actions have to be established within the similar species and different types of secondary metabolites identified by the plant callus. [Riaz S, Malook SU, Shah AH, Sarfaraz M, Kazmi SMZ, Abad Z, Jabeen S, Zamsn RQU, Asif M, Ali Q. Improvement of secondary metabolites for Cucurbita moschata through tissue culture techniques: An overview. Life Sci J 2015;12(4s):94-101]. (ISSN:1097-8135). http://www.lifesciencesite.com. 13

Drought tolerance is a polygenic trait, with a complicated phenotype, often confused by plant phenology. Breeding for water stress is more complex since many types of abiotic stress, such as drought, heat and salt. High yielding wheat genotypes viz., Miraj-06, 9452, 9469, 9272, 9277, CMS-127 and three testers Chakwal-50, Kohistan-97 and Aas-11 were crossed in line × tester mating design. Seed obtained from crosses was evaluated in field conditions for various agronomic traits under drought conditions. Recorded data were subjected to analysis of variance to determine the genetic variability. The data were analyzed statistically and combining ability studies were tested using line × tester analysis to find the relationship between different traits of wheat. High significant differences were observed among the lines and testers for yield related traits under stress conditions. The female line 9452 proved to be best line on the basis of mean performance of traits under water stress. In case of testers, the male parent variety Chakwal-50 retained its performance in maximum number of traits closely followed by Aas-11. The cross combination 9272 × Aas-11 proved best for attaining highest mean for most of traits. In case of GCA effects line 9277 and tester Aas-11 proved best. The cross combinations 9277 × Chakwal50, 9452 × Kohistan-97 exhibited highest SCA effects. The superior genotypes and crosses can be combined to develop new promising and improved varieties under water stress conditions.

Abiotic stresses like drought, salinity and high temperature are the major problems, which reduce rice crop yield world-wide. Among them drought is most yield limiting factors, which significantly affect its growth, development and lower its yield. Developing drought tolerant rice genotypes is dire need of the time, pre-requisite of which is availability of genetic variation and diversity. The present review describes the methodologies to devise easy, quick and cost effective screening protocols for assessment of genetic variation against drought stress to know stress responsive traits while keeping in view the erratic nature of this crop against abiotic stress drought. The role of various transcriptional factors will also be discussed to understand the mechanism of control against drought. [Masood SA, Sofia J, Madiha A, Zain N, Anum J and Qurban Ali. Genetic Association of transcriptional factors (OsAP2 gene family) to incorporate drought tolerance in rice (Oryza sativa L. ssp. indica): An overview. Life Sci J 2015;12(3s):71-76]. (ISSN:1097-8135). http://www.lifesciencesite.com. 12