N-deficiency damps out circadian rhythmic changes of stem diameter dynamics in tomato plant

Abstract

Tomato (Lycopersicon esculentum) plants were grown in hydroponics. At the fruiting stage, N was withdrawn from the growing medium for a period of 19 days and its effects were studied on plant biomass production, photosynthesis, partitioning of 13 C and 15 N, and changes in the stem and fruit diameters etc, in order to monitor the mechanism of resource management on the plant parts at low N and prevent excess use of the fertilizer. N-deficiency treatment decreased leaf photosynthesis immediately and affected biomass accumulation of tomato. Conversely, N-deficiency increased stem diameter for a period of two weeks before reducing it below the control. During this period, these results suggest that N deficiency more suppress source activity than sink activity. N-deficiency reduced the amplitude of the circadian pattern of daytime shrinkage and nocturnal expansion of the stem diameter by decreasing the magnitude of the former. Circadian pattern of contraction and expansion of diameter was less evident in the fruit. Under N-deficiency, distribution of 13 C and 15 N decreased and increased to fruits respectively. Restricted partitioning of carbon to fruits could be responsible for accumulation of unused assimilates and consequential osmotic adjustment for maintenance of stem water potential. This effect might have precluded contraction of stem diameter of N-deficient plants until the production of assimilates became limiting on account of depression of leaf photosynthesis.

Growth, nutrient concentration, nutrient accumulation and visual symptoms of nutrient deficiencies in cherry tomato plants

“…N is part of the chlorophyll compound, so its lack compromises the chlorophyll content in the plant, which is related to the occurrence of chlorosis, as observed in cherry tomato leaves. N deficiency severely decreases chlorophyll content, photosynthesis, biomass accumulation and tomato plant growth (KANAI et al, 2008;KHAVARI-NEJAD et al, 2009).…”

Genetic analysis of rootstock-mediated nitrogen (N) uptake and root-to-shoot signalling at contrasting N availabilities in tomato

“…Since past tomato breeding programs grew plants under optimal (N-sufficient) conditions, this genetic variability has been likely lost in the domestication process. Thus, N-deficiency severely decreases chlorophyll content, leaf photosynthesis, biomass accumulation, and growth of current tomato cultivars [9,10].…”

Traceability along the production chain of Italian tomato products on the basis of stable isotopes and mineral composition

“…In particular, Bong et al 24. measured the δ 18 O and δD of vegetal water in fast‐ and slow‐growing fruits proving that fast‐growing fruits such as the tomato experience much stronger evaporation than slow‐growing fruits whereas Kanai et al 25. showed that the δ 13 C and δ 15 N of tomato fruits have an opposite trend in the case of N‐deficiency.…”

“…Other studies have focused on the differences in stable isotope ratios in tomato plants or in stressful situations. [23] In particular, Bong et al [24] measured the d 18 O and dD of vegetal water in fast-and slow-growing fruits proving that fast-growing fruits such as the tomato experience much stronger evaporation than slow-growing fruits whereas Kanai et al [25] showed that the d 13 C and d 15 N of tomato fruits have an opposite trend in the case of N-deficiency. Pfammatter et al [26] used the d 18 O of vegetal water to discriminate Swiss tomatoes originating from different cantons and to discriminate Swiss tomatoes from foreign fruits.…”