Screening of pigeonpea genotypes for nutrient uptake efficiency under aluminium toxicity

Abstract

For increasing pigeonpea production in India, it is necessary to expand its area in non-traditional areas such as north-eastern states, which have considerable area under acidic soils. In such soils, aluminium toxicity, which is a major yield limiting factor, interferes with nutrient uptake efficiency of crop plants. 32 genotypes of pigeonpea [Cajanus cajan (L.) Millsp.] were screened for tolerance to aluminium toxicity at four different aluminium concentrations (41, 82, 123 and 205 μM Al) by hematoxylin staining and root re-growth methods. The results of the two screening methods were consistent, suggesting that either of the two methods could be used for screening purpose. The most tolerant (IPA 7-10, T 7, 67 B and GT 101E) and sensitive (Bahar, Pusa 9 and Pusa 2002-2) genotypes were assessed for root and shoot aluminium contents in hydroponic assay at 0, 41, 82, 123 and 205 μM aluminium concentrations. Root and shoot aluminium contents were significantly lower in the tolerant than sensitive genotypes, indicating that aluminium tolerance mechanism involved aluminium exclusion and perhaps internal detoxification. Tolerant and sensitive genotypes were further assessed for phosphorus, potassium, calcium and magnesium contents in their root and shoot. Tolerant genotypes (IPA 7-10, T 7, 67 B and GT 101E) accumulated significantly high amounts of these nutrients (>1.5 times) compared to the sensitive ones. Better performance of tolerant genotypes could be ascribed to better nutrient uptake efficiency and distribution within the plants.

Time Series RNA-seq in Pigeonpea Revealed the Core Genes in Metabolic Pathways under Aluminum Stress

“…It can be used as food, feed, fuel wood, green manure, and hedges. In addition, it also plays an important role in insect reproduction, soil and water conservation, and so on [1,2]. It is distributed in Asia, Eastern and Southern Africa, Latin America, and Caribbean countries, and its maturity has a large temporal variation [1,3].…”

“…Collectively, our findings not only revealed the regulation mechanism of pigeonpea under Al stress but also provided methodological support for further exploration of plant stress regulation mechanisms.Low phosphorus (P) levels and aluminum (Al) toxicity are two major adverse factors in acidic soil, which, together, restrict crop growth [4][5][6][7]. Aluminum toxicity is a serious problem that threatens crop productivity in acidic soil [2,8,9]. Many crops can be influenced by Al, and the growth of roots and shoots can be limited by it [9][10][11].…”

“…Through the analysis of the absorption efficiency of nutrients under Al stress, genotypes with good tolerance to Al stress have been found. Tolerant genotypes (IPA 7-10, T7, 67 B, and GT 101E) accumulate significantly high amounts of nutrients (>1.5 times) compared with sensitive genotypes [2]. Except for the absorption of nutrients, metabolic changes are also vital processes under Al stress.…”

“…Additionally, Arabidopsis, as a model plant, has also provided a research basis for Al stress [15][16][17]. Al stress in Arabidopsis, rice, tomato, and pigeonpea has been found to cause aluminum-dependent root growth inhibition [2,6,17]. In addition, the transcription factors STOP1 in Arabidopsis and CcSTOP1 in pigeonpea have been proved to play an important role in regulating Al resistance [11,16].…”

METHOD FOR RAPID ASSESSMENT OF ALUMINUM TOLERANCE OF PEA (Pisum sativum L.)

“…In particular, cell division [14], membrane pectin fermentation [15], and the synthesis of actin for root cell cytoskeleton formation are damaged [16]. Further, inhibition of the initiation and growth of lateral roots and root hairs and a breach of plant supply with minerals and water take place [12,17]. The problem of acidic soils is solved based on two approaches, i.e., through soil liming (an expensive and not always effective method) and by creation of acid resistant plant varieties, helped by a significant intra-specific variation of the aluminum tolerability in crops and relatively simple schemes for screening and selection [5,18].…”