Grafting to improve nitrogen‐use efficiency traits in tobacco plants

Abstract

Nitrate plays a major role in the yield and quality of tobacco plants. This work explored the nitrogen-use efficiency (NUE) and how it can be affected by grafting. Two experiments were designed: in the first, using six commercial tobacco cultivars, the best cultivar for the NUE was selected and analysed for foliar NO 3 − content, total N, nicotine and nitrate reductase (NR) activity. The results showed the cultivar H-20 to have the best performance on NUE. It was further featured by the highest NR activity and total N and by the lowest NO 3 − and nicotine content, resulting in the highest foliar leaf biomass production and quality. In the second experiment it was tested whether the cultivar H-20 could be used as rootstock to improve the NUE of the other cultivars under study. The results showed that the grafted plants had improved the NO 3 − assimilation with respect to non-grafted plants. Hence grafting tobacco plants can be used as a quick and effective method to improve NUE, which has beneficial implications for human health and for a reduction in environmental pollution.

Nitrogen Use Efficiency and Yield in Response Graft Bell Pepper Cultivars

“…This fact agreed with the previous findings about the use of rootstocks. Grafted plants usually had lower N and NO 3 − levels in leaf tissue, indicating that these parameters are significantly influenced by the scion-rootstock interaction and by the rootstock (Ruiz et al, 2006;Del Amor et al, 2008). Although we did not detect significant differences in the levels of leaf N between grafted plants, it is clear than this situation did not produce a negative affected in the N metabolism and crop yield of these cultivars.…”

“…- (Pulgar et al, 2000;Ruiz et al, 2006). Apparently, the efficient use of N shown by grafted pepper plants produced an increase of fruit yield, as reported by other studies (Del Amor et al, 2008;De Charlo et al, 2012;Yasuor et al, 2013).…”

“…3, Panel B), 'Orangela' and 'Fascinato' were the two grafted genotypes than showed the highest values, with respect to the rest of genotypes studied ('Jannette' and 'Sweet'). NR endogen activity it is considered an indicator of leaf NO 3 -concentration, thus this condition of high endogen activity to allow a favorable NO 3 -accumulation in leaf of these grafted cultivars; therefore, the NO 3 -bioavailable required for a more active N metabolism and fruit production (Pulgar et al, 2000;Ruiz et al, 2006). Apparently, the efficient use of N shown by these grafted bell pepper plants produced an increase of fruit yield, as reported by other studies (Del Amor et al, 2008;De Charlo et al, 2012;Yasuor et al, 2013).…”

Variation in the use efficiency of N under moderate water deficit in tomato plants (Solanum lycopersicum) differing in their tolerance to drought

“…Reduced N is the product of NO 3 -assimilation and is used as structural, functional, and storage amino acids and proteins. Besides, TNC is a determining parameter in the nutritional state of plants, since it represents the sum of the organic and inorganic forms of N (Ruiz et al 2006). Therefore, we can state that, under water stress, cv.…”

“…This can be divided into two fundamental processes: (1) the ability of the plant to take up N from the soil, and (2) the utilization efficiency of the N taken up, i.e. the ability of the plant to transfer this element to plant organs (Lea and Azevedo 2006;Ruiz et al 2006). Genetic variability regarding NUE has been demonstrated in several species, such as rice, alfalfa, and maize (Harrison et al 2004;Lawlor 2002;Machado and Fernandes 2001).…”