L. Romero et al., RESPONSE OF PLANT-YIELD AND LEAF PIGMENTS TO SALINE CONDITIONS - EFFECTIVENESS OF DIFFERENT ROOTSTOCKS IN MELON PLANTS (CUCUMIS-MELO L.), Soil Science and Plant Nutrition, 43(4), 1997, pp. 855-862
Two varieties of Cucumis melo (Resisto and Arava) were grafted onto th
ree hybrids of Cucurbita maxima and Cucurbita moschata cultivars (Shin
toza, RS-841 and Kamel). Ungrafted Cucumis melo var. Resisto and var.
Arava plants were used as controls. Plants mere grown under controlled
greenhouse conditions and were constantly fertilized with macro-and m
icronutrients, supplied with irrigation water rich in Na+ and Cl-. Con
tents of chlorophylls a and b, carotene pigments, Cl- and total and so
luble Na+ and K+ ions were measured in all the scion parts of the plan
ts. The results showed that grafted plants exhibited differences in th
e leaf content of Naf and especially Cl- in comparison with ungrafted
plants. In addition, yield as well as leaf pigments appeared to be goo
d indicators of Cl- levels in scion parts. It is assumed that grafted
plants developed various mechanisms to avoid physiological damage caus
ed by the excessive accumulation of these ions in leaf, including the
exclusion of Cl- ion and/or decrease in Cl- absorption by the roots an
d the replacement or substitution of total K+ by total Na+ in the foli
ar parts.