Effect of salinity on physiological characteristics, yield and quality of microtubers in vitro in potato

Abstract

Ab stractIn vi tro microtuberization pro vides an ad e quate ex per i men tal model for the phys i o log i cal and met a bolic stud ies of tuberization and the pre lim i nary screen ings of po ten tial po tato geno types. The ef fects of sa line stress at 0-80 mmol con cen tration on in vi tro tuberization of two po tato cultivars were in vesti gated in this study. With an in crease in the salt con cen tra tion, the microtuberization of po tato was ei ther de layed by 5-10 days (20 and 40 mmol NaCl) or in hib ited com pletely (80 mmol NaCl) in ad di tion to the re duc tion in microtuber yields. The two po tato ge no types stud ied showed dif fer ent trends in to tal sol u ble sug ars, su crose and starch con tents of microtubers under NaCl stress, while glu cose and fruc tose lev els re mained un changed. The vi ta min C con tent in microtubers of two potato ge no types was re duced by salt stress. Sa lin ity ap plied from 20 to 60 mmol pro gres sively in creased proline and malondi aldehyde (MDA) lev els in microtubers of both the potato cultivars. In ge no type Zihuabai, NaCl at a low con cen tration (20 mmol) led to a sig nif i cant in crease in peroxidase (POD) and polyphenoloxiadase (PPO) ac tiv i ties, while in Jingshi-2, the PPO ac tiv ity de creased pro gres sively with an increase in NaCl con cen tra tions. Ge no type Zihuabai ex hib ited higher tol er ance to salt stress than Jingshi-2 un der in vi tro condi tions. These re sults could be used for pre lim i nary se lec tions of salt tol er ance in po tato breed ing programmes. In tro duc tionStud ies on soil sa lin ity or sa line wa ter are gain ing im por tance in ag ri cul ture be cause it af fects the growth and de vel op ment of crops by creating a stress and thereby re sults in yield loss. Salt stress in duced var i ous bio chem i cal and phys i o log i cal responses in plants and af fected al most all plant processes in clud ing pho to syn the sis, growth and de vel op ment (Nemoto and Sasakuma 2002). Sa linity tol er ance by plants de pends pri mar ily on the geno type that de ter mined al ter ations on pro cesses such as up take and trans port of salt by roots, together with met a bolic and phys i o log i cal events (Winicov 1993). Screen ing of dif fer ent cultivars for abiotic stress tol er ance was nec es sary not only for breed ing of po tato to abiotic stress, but also for pro vid ing better ma te rial for study ing the abiotic stress tol er ance mech a nism (Sergeeva et al. 2000).Po tato is clas si fied as one of mod er ately sen si tive crops of sa lin ity tol er ant group (Katerji et al. 2003).

In Vitro Screening of Different Potato Genotypes for Salinity Tolerance

“…These differences were expected due to the different genetic back ground, breeding origin, and maturity group of the examined genotypes. In harmony with our results, several reports demonstrated genotypic differences in salt tolerance in potato (Kharis et al, 1998;Zhang et al, 2005;Sudhersan et al, 2012).…”

“…The observed decreases in microtuberization under salt stress are in agreement with the results of Zhang and Donnelly (1997) and Zhang et al (2005). Under the conditions of this study, significant differences among potato genotypes were found, in response to in vitro salt stress.…”

“…In most of the previous reports, the in vitro screening of potato genotypes for salt stress was conducted in limited number of potato varieties, and bioassays were based on either plantlet growth from single node segments (Rahman et al, 2008) or microtuber formation under salt stress (Zhang et al, 2005). In our study, it was possible to examine 29 potato cultivars and breeding clones, most of them are recently introduced to the Egyptian growers.…”

Evaluating asymbiotic seed culture methods and establishing Disa (Orchidaceae) germinability in vitro: relationships, requirements and first-time reports

“…For example, salt stress has been shown to inhibit the growth of plant seedlings and roots in rice and wheat (Lin and Kao 1996;Xia et al 2000;Zhu et al 2002), as well as affecting the leaf chlorophyll and photosynthetic functions in sweet potato and wheat (Ke and Pan 1999;Zhu et al 2002). Salinity can also induce the accumulation of proline and malondialdehyde (MDA) in rice and potato (Lin and Kao 1996;Martinez et al 1996;Zhang et al 2005a) and change the activities of various antioxidant enzymes in several crops (Sairam and Srivastava 2002;Rios-Gonzalez et al 2002;Meloni et al 2003).…”

Effect of jasmonic acid on in vitro explant growth and microtuberization in potato

“…Tuberization in potato was controlled by the tuberonic acid and its glucosides which had a close relation with JA in structure (Koda and Okazawa 1988, Yoshihara et al 1989). In addition, in vitro microtuberization provided an adequate experimental model for the physiological and metabolic studies of tuberization and the screening of potential potato genotypes (Li et al 2004, Zhang et al 2005a. The purpose of this work was to investigate the effects of different concentrations of JA on the growth and development of potato plantlets and microtubers under in vitro conditions.…”