Relationship between total sulphur and sulphur amino acids in chickpea (Cicer arietinum L.) and pigeonpea (Cajanus cajan [L.] Millsp.)

Total sulphur was determined in seed meal of 30 chickpea and 24 pigeonpea cultivars by the wet digestion procedure and by using the Leco sulphur analyser. Methionine and cystine were determined after performic acid oxidation in an amino acid analyser. The two methods used for total sulphur determinations were highly correlated (r=0.943). Percent meal protein was significantly correlated (r=0.476) with total sulphur in chickpea but not in the case of pigeonpea. Total sulphur content exhibited a significant positive correlation (r=0.651) with sulphur amino acids of pigeonpea when expressed as percent of protein but not in the case of chickpea. Correlation coefficients between total sulphur and sulphur amino acids when the results were expressed as percent of sample were positive for both chickpea (r=0.494) and pigeonpea (r=0.534). The amount of sulphur in methionine and cystine accounted for 54.8% of the total sulphur in chickpea and for 75.5% in pigeonpea. In both chickpea and pigeonpea, methionine was positively and significantly correlated with cystine when they were expressed either as percent of sample or as percent of protein.Submitted as J.A. no. 159 by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT).     

Factors affecting the protein quality of pigeonpea (Cajanus cajan L.)

Pigeonpea occupies an important place in human nutrition as a source of dietary proteins in several countries. Some of the important factors that affect the protein quality of pigeonpea have been reviewed and summarised in this paper. Among important food legumes, pigeonpea contained the lowest amount of limiting sulphur amino acids, methionine and cystine implicating the importance of these amino acids in protein quality improvement program. Large variation existed in the levels of protease inhibitors of pigeonpea varieties. The concentration of these inhibitors were significantly higher in some of the wild relatives of pigeonpea. Protein digestibility of cooked pigeonpea meal remained low and this could be due to the presence of certain compounds other than trypsin inhibitors. Pigeonpea polyphenolic compounds adversely affected the activity of digestive enzymes and this would affect the protein quality of pigeonpea. The protein quality of pigeonpea was greatly influenced by storage and processing practices.     

Seed protein fractions and amino acid composition in gram (Cicer arietinum)

Six chickpea strains were analysed for their protein content and various protein fractions. The protein content ranged from 20.9–25.27%. Albumin, globulin, prolamin and glutelin contents ranged from 8.39–12.31%; 53.44–60.29%; 3.12–6.89% and 19.38–24.40% respectively. Salt soluble proteins (albumin + globulin) and globulins resolved into 19–23 bands whereas albumin proteins resolved into 30–34 bands. The molecular weights of various polypeptides ranged from 10–91 kD. Amino acid analysis of total proteins revealed that glutamic acid was present in maximum concentration followed by aspartic acid and arginine. Just like other pulse proteins, chick pea proteins were also found deficient in sulphur containing amino acids.     

Mineral and trace element composition in induced mutants of pigeonpea (Cajanus cajan (L.) millsp.)

In the present investigation several mutants isolated during mutagenic studies of pigeonpea were analysed for Ca, Mg, Fe, Zn, Cu, Mn, Cr, Ni. The results have revealed changes in the concentrations of macro and micro mineral elements in the mutant seed material. These changes in concentrations are attributed to the altered genetic structure; due to mutations, the plant system might have absorbed and stored more or less amounts of the elements in the seeds.     

Chemical composition and nutritional value of Mexican varieties of chickpea (Cicer arietinum L.)

Chemical composition and protein quality of the main chickpea varieties cultivated in Mexico were determined. The raw and cooked chickpeas analyzed were: Surutato, Surutato 77, Sonora, Sonora 80, Porquero, Macarena, Breve Duro and a mixture of broken seeds used mainly for animal feeding. The chemical composition of the raw chickpea studied was very similar; the average values of the nutrients were: ash 3.1±0.2, fat 5.0±1.0, protein 19.5±1.2 and fiber 3.7±2.1. Cooking diminished only the ash content and the Porquero variety was the only one that had a high content of crude fiber (9.1%). There was not found agglutinating activity to rabbit RBC in any of the raw chickpeas studied and the trypsin inhibitor activity average was 11.8±2.4 TUI/mg sample. Cooking destroyed 57% of this activity. Digestibility was the same in the raw and in the cooked chickpea (78%). There were not found significant differences in the PER values of the raw and cooked seeds: 1.65–2.30 and 1.80 to 2.61 respectively. The Surutato and Breve Duro varieties were statistically similar to the casein PER (2.5). It could be recommended to use these two varieties mainly for infant feeding.     

The protein content of chickpea (Cicer arietinum L.) grown at different locations

Plant Foods for Human Nutrition - Seed protein content was determined in several genotypes of chickpea grown at different locations in India in different years. Statistical analysis showed that...     

Inheritance of protein content and its correlation with grain yield in pigeonpea (Cajanus cajan (L.) Millsp.)

Four lines of pigeonpea (Cajanus cajan (L.) Millsp.) ware selected for variability in protein content and were used as parents in crosses. The F₂ mean protein contents were generally between the parents, but slightly closer to the low-protein parent. Reciprocal differences in protein of F₁ seeds and its absence in F₂ seeds showed that the maternal genotypes controlled protein content.The broad sense heritability estimates varied from 34 to 62 per cent in different crosses. These low and variable values indicate high environmental-influence on protein content and relatively low additive genetic variance. A minimum of 3 or 4 genes control protein content. Low protein was partially dominant over high protein.Grain yield and protein content were negatively correlated in F₂ plants from crosses between low and high protein lines. Grain yield and protein yield were highly correlated. It is suggested that for total protein production per unit area efforts should be directed towards increased seed yield while maintaining per cent protein near average levels rather than by selecting for high protein in the grains alone.

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Zusammenfassung Vier Linien der Strauch- oder Taubenerbse (Cajanus Cajan (L.) Milsp.) wurden auf Variabilität des Eiweißgehalts ausgelesen und als Eltern für Kreuzungen benutzt. Die F₂-Generation mit mittleren Eiweißgehalten lag im allgemeinen zwischen den Eltern aber doch etwas näher an den Eltern mit niedrigen Eiweißgehalten. Reziproke Verschiedenheiten im Eiweiß der F₁-Samenkörner und seine Abwesenheit im F₂-Samen zeigte, daß der Genotyp der Mutter die Höhe des Eiweißgehalts kontrolliert.Die breitgefächerten Vererbungen zeigen Variationen von 34 zu 62 % bei verschiedenen Kreuzungen. Diese niedrigen und variablen Werte zeigen den großen Einfluß der Umweltfaktoren auf den Eiweißgehalt und relativ wenig additive genetische Varianz. Nur ein Minimum von 3 oder 4 Genen kontrolliert die Höhe des Eiweißgehalts. Niedriger Eiweißgehalt war teilweise dominant über hohen.Samenertrag und Eiweißgehalt waren in F₂-Pflanzen negativ korreliert und zwar bei Kreuzungen zwischen Linien mit niedrigen und hohen Eiweißgehalten. Samenertrag und Eiweißertrag waren hochkorreliert. Es müssen zur Eiweißproduktion je Flächeneinheit Anstrengungen gemacht werden, um höhere Samenerträge zu erzielen, wobei der Eiweißgehalt eher nahe eines mittleren Wertes gehalten werden sollte als durch Selektrion hohe Eiweißgehalte in den Körnern zu gewinnen.

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A part of the All India Co-ordinated Research project for improvement of Pulses, financed by Indian council of Agricultural Research.     

Nutritional quality of chickpea (Cicer arietinum L.): current status and future research needs

The nutritional composition and the affects of processing and storage and anti-nutrients on nutritional value of chickpeas are reviewed. Future research needs are discussed.Submitted as J.A. No. 431 by the International Crops Research Institute for the Semi-Arid Tropics (ICRASAT).     

Variability of root length density and its contributions to seed yield in chickpea (Cicer arietinum L.) under terminal drought stress

The importance of root systems in acquiring water has long been recognized as crucial to cope with drought conditions. This investigation was conducted to: (i) evaluate the variability on root length density (RLD) of chickpea in the vegetative growth stage; (ii) estimate the effect of RLD on seed yield under terminal drought conditions; and (iii) set up a procedure to facilitate the screening of chickpea genotypes with large RLD. Twelve diverse chickpea genotypes were grown in tall PVC cylinders with two different soil water treatments in 2000 and 2001, and in field under water deficit conditions during 2000/2001 and 2001/2002. In field trials, the mean RLD at 35 days after sowing showed a significant positive correlation with seed yield in both years. Similarly, the RLD in the 15–30 cm soil depth had significant positive effects to the seed yield in both years. The importance of the root trait was particularly relevant in 2001/2002, a more severe drought year, when the RLD in deeper soil layer, 30–60 cm depth, showed a significant positive relationship with seed yield. Also, the RLD at deeper soil layer, 30–60 cm depth, was higher in 2001/2002 than in 2000/2001, in particular in tolerant genotypes. The PVC cylinder trials were set up to facilitate the screening of chickpea genotypes with large RLD. RLD of plants grown in cylinders with 70% field capacity was correlated with RLD in the field trials (r = 0.731; p = 0.01). This work highlights the importance of roots in coping with terminal drought in chickpea. The cylinder system offers a much easier procedure to screen chickpea genotypes with large RLD.     

Limiting amino acids in raw and processed amaranth grain protein from biological tests

Amino acid supplementation studies with young rats were carried out using raw and processed amaranth grain (A. cruentus) of dark- and cream- or light-colored seeds. The results of various studies repeatedly indicated that threonine is the most limiting amino acid in raw and processed, dark and cream-colored grain. Protein quality as measured either as NPR or PER was improved by threonine addition alone or with other amino acids and decreased liver fat to values similar to those measured with casein. This finding contradicts the reports that state that leucine, determined by chemical score, is the most limiting amino acid. Leucine addition alone or with other amino acids did not improve protein quality. The study confirmed cream-colored grain to be nutritionally superior to dark grain and that properly processed grain, light- or dark-colored, has higher protein quality than raw grain.INCAP Publication I-1525     

Dry heat popping of amaranth seed might damage some of its essential amino acids

Amaranth was a major crop among the Aztecs. In Mexico the seed is popped and eaten with brown sugar. The crude protein content of the seed is 14±2% but its contents of lysine and tryptophan are 6.2 and 1.6 g/16 g N respectively. We developed a popping method based on a fluid bed system (FBS) whereas the traditional method (TM) is just to pop the seeds manually in a hot plate. Assays carried out were evaluation of racemization of the amaranth protein due to heat treatment, amino acid composition of the raw and heat treated seeds and a biological experiment testing whether leucine was the most limiting amino acid of amaranth protein. Male rats were fed both popped amaranths and roasted amaranth. Parboiled amaranth and casein were controls. The results were: (a) Lys, Arg and Cys were damaged in the heat treated seeds; (b) Asp, Met, Glu, Ala and Phe were racemized in that decreasing order in the seeds popped and roasted by the TM; (c) the estimated net protein retention (NPR) and estimated net protein utilization (NPU) of popped amaranths by either method were not different, but were lower than for the parboiled amaranth. The parboiled amaranth was not different from casein; (d) Leu was not the most limiting amino acid in any of the amaranth seeds tested. After Lys, sulfur amino acids appear to be the next most limiting in severely heat treated amaranth. The FBS seems to be a promising method for popping amaranth at industrial level.     

Nutritional composition and antinutritional factors of chickpeas (Cicer arietinum L.) undergoing different cooking methods and germination

The effects of cooking treatments (boiling, autoclaving and microwavecooking) and germination on the nutritional composition and antinutritionalfactors of chickpeas were studied. Cooking treatments and/or germinationcaused significant (p < 0.05) decreases in fat, total ash, carbohydratefractions, antinutritional factors, minerals and B-vitamins. Germination wasless effective than cooking treatments in reducing trypsin inhibitor,hemagglutinin activity, tannins and saponins; it was more effective inreducing phytic acid, stachyose and raffinose. Cooking treatments andgermination decreased the concentrations of lysine, tryptophan, totalaromatic and sulfur-containing amino acids. However, cooked andgerminated chickpeas were still higher in lysine, isoleucine and totalaromatic amino acid contents than the FAO/WHO reference. The lossesin B-vitamins and minerals in chickpeas cooked by microwaving weresmaller than in those cooked by boiling and autoclaving. Germination resultedin greater retention of all minerals and B-vitamins compared to cookingtreatments. In vitro protein digestibility, protein efficiency ratio andessential amino acid index were improved by all treatments. The chemicalscore and limiting amino acid of chickpeas subjected to the varioustreatments varied considerably, depending on the type of treatment. Basedon these results, microwave cooking appears to be the best alternative forlegume preparation in households and restaurants.     

Changes in trypsin and chymotrypsin inhibitory activity on soaking of redgram (Cajanus cajan L.)

Changes in trypsin and chymotrypsin inhibitory activity of redgram seeds on soaking in distilled water, different salt solutions and mixed salt solution were investigated. Reduction in trypsin and chymotrypsin inhibitory activity was observed on soaking in salt solutions in comparison to soaking in distilled water. Maximum loss of trypsin and chymotrypsin inibitory activity was observed on soaking the seeds in mixed salt solution.     

The composition of pigeon peas (Cajanus cajan (L. Millsp.) grown in Botswana

This study investigated the composition of pigeon peas (Cajanus cajan),grown at Sebele, Botswana. The raw seeds of six varieties were analyzed fordry matter, crude fat, protein, fiber, and ash, using Association of OfficialAnalytical Chemists procedures. Major minerals, Ca, K, P, Mg, Na and traceminerals, Cu, Fe and Zn were also assessed. The range of nutrient contentsobtained were: dry matter 86.6–88.0%, crude protein 19.0–21.7%, crudefat 1.2–1.3%, crude fiber 9.8–13.0%, and ash 3.9–4.3%. Minerals ranges(mg/100 g dry matter) were: K 1845–1941, P 163–293, Ca 120–167, Mg 113–127, Na 11.3–12.0, Zn 7.2–8.2, Fe 2.5–4.7 and Cu 1.6–1.8. There wereno significant differences in Na among the six varieties (p>0.05). For the other components, varietal differences (p < 0.05) were observed. The valuesobtained for the dry matter, crude protein, fat, ash, Ca, Cu, Fe, and Mg weresimilar to those in pigeon peas grown elsewhere, while those for crude fiber and Zn were higher. In general, the composition of pigeon peas compared favorably with those of other legumes such as Bambara groundnut (Vignasubterranea). The levels of crude protein, crude fiber, K, Ca, P and Mgindicated that pigeon peas could be valuable in the diet of the people of Botswana. This crop would positively contribute protein in the diet and thediversification of agricultural produce.     

Amino acid compositions of different protein fractions in developing grains of NP 113 barley and its high lysine Notch-2 mutant

The percent distributions of protein fractions namely albumin + globulin, prolamine and glutelin were studied in developing grains of NP 113 barley and its high lysine mutant Notch-2. During development the percentage of albumin + globulin fraction decreased in NP 113, while those of prolamine and glutelin remained unchanged. The increase in prolamine was substantial from 24 to 31DAA. In Notch-2 the trend followed by albumin + globulin and prolamine was like that in NP 113, while the glutelin fraction showed an increase as compared to 10 DAA. The percent of albumin + globulin was slightly higher in Notch-2 as compared to NP 113. The absolute amount (mg/grain) of all the protein fractions increased during development in both NP 113 and its mutant Notch-2. During the grain development the prolamine content was substantially lower in the mutant than in the parent NP 113. The albumin + globulin content per endosperm was in general also higher in NP 113 than Notch-2. Amino acid analysis of the protein fractions did not reveal significant changes in lysine between NP 113 and Notch-2. Thus, the improvement in lysine in the mutant is primarily due to reduced synthesis of the prolamine fraction and not due to an increase in lysine in the mutant hordein fraction. Part of the improvemenht in lysine may also be due to increase in the percentage of albumin + globulin fractions which is lysine rich.Part of the Ph.D thesis submitted by S. Joshi to P.G. School, IARI, New Delhi.     

Multi-environment field testing for identification and validation of genetic resistance to Botrytis cinerea causing Botrytis grey mold in chickpea (Cicer arietinum L.)

Botrytis grey mould (BGM), caused by Botrytis cinerea Pers. Ex. Fr., is a destructive foliar disease of chickpea (Cicer arietinum L.) worldwide. Disease management through host-plant resistance is the most effective and economic option to manage this disease. The objective of this study was to identify new sources of resistance to BGM, validate their stability across environments and determine the magnitude of G × E interaction. One hundred and nine chickpea genotypes with moderate levels of resistance (BGM severity ≤5.0 on a 1–9 scale) were selected from the preliminary evaluation of 412 genotypes including germplasm and breeding lines under controlled environmental conditions in 2004–2005 at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, India. In order to validate resistance stability, an ‘International Botrytis Grey Mould Nursery’ (IBGMN) was constituted with 25 genotypes and tested in multi-environments for BGM resistance at two locations (Gurdaspur and Pantnagar) in India for 4 years and two locations (Tarahara and Rampur) in Nepal for 3 years. Additive main effects and multiplicative interaction (AMMI) analysis showed significant genotype (G), environment (E) and G × E interaction (p < 0.0001) with largest contribution by environment (47.36%). The first two principal component axes were significant, and contributed 48.21% to the total G × E interaction. The AMMI biplot analysis allowed the selection of five genotypes ICCV 96859, ICCV 96853, ICCV 05604, ICCV 96852 and ICCV 05605 with low BGM severity (between 3.7 and 4.7 on 1–9 scale) and moderate stability. Genotype ICCV 96859 having least disease severity and moderate stability could be highlighted and exploited in chickpea resistance breeding programmes.     

木豆育种及分子生物学研究进展

木豆为豆科木豆属多年生常绿小灌木,是世界第六大食用豆类,也是唯一的木本食用豆类。木豆用途非常广泛,成熟籽实可以食用,营养价值丰富;嫩枝叶是草食家畜的优质饲料,又可用作水土保持和覆盖作物等。木豆对土壤条件要求不严,适合世界热带亚热带地区种植。本文介绍国内外木豆育种及分子生物学研究概况和进展,并对国内今后木豆研究提出展望。     

Irradiation and germination effects on phytate,protein and amino acids of soybean

Influence of irradiation (0.05–0.20 kGy) and germination (24–120 hours) in distilled and tap water on phytate, protein and amino acids of soybean, was studied. Phytate values significantly decreased with increasing germination period and irradiation dose (P<0.01). Irradiation independently decreased the original phytate (212.0 mg/100 g) to a range value of 205.0–190.0 mg/100 g depending upon dose level. Germination of unirradiated seeds for 120 hours in distilled and tap water lowered the phytate to 55.0 and 94.9 mg/100 g (74.1 and 55.2% reduction) respectively. Maximum destruction of phytate to levels of 20.5 and 50.9 mg/100 g (90.3 and 76.0% reduction) occurred during germination of 0.20 kGy samples for 120 hours in distilled and tap water respectively. Total protein content significantly increased during germination (P<0.05) and the increase was more in tap than distilled water. Germination for 120 hours of untreated seeds in tap water increased the essential and decreased non-essential amino acids while in the 0.10 kGy sample, increases in both cases were observed.     

Nutritive value of rapeseed proteins and fractions supplemented with methionine and tyrosine in rats

Rapeseed protein concentrate (RPC), rapeseed 2S and 12S fractions, a blend of 2S and 12S fractions, retentate (RET) and precipitate (PRE) proteins obtained during rapeseed fractionation were compared to casein for nutritive value as determined by net protein ratio (NPR) and apparent digestibility coefficient (ADC). Tyrosine concentration in rapeseed 2S fraction was the lowest compared to all other protein sources and methionine was the first limiting amino acid. The NPR and ADC of RPC, RET, and fraction 12S did not change significantly (P<0.05) following supplementation with methionine, but for PRE the NPR was decreased significantly (P<0.05). However, the rapeseed 2S fraction supplemented with tyrosine had a NPR significantly (P<0.05) higher than that of RPC and not significant (P<0.05) different from that of casein. The NPR of the 2S and 12S blend was significantly (P<0.05) higher than that of RET and PRE; however, no significant (P<0.05) difference was observed in NPR and ADC of the blend when supplemented with tyrosine. The nutritive value and digestibility of rapeseed 2S fraction were improved by supplementation with tyrosine and by blending with the 12S fraction.     

Changes in starch,oil, protein and amino acids in developing seeds of okra (Abelmoschus esculentus L. Moench)

The okra seeds of variety Pusa sawani were analysed for protein, non-protein nitrogen, total free amino acids, lysine, and tryptophan from the 7th day to the 42nd day after flowering. Starch, total sugars and oil percent were also estimated in these seeds. During the early stages of maturation, the soluble components (non-protein nitrogen, free amino acids and total sugars) were found in higher quantities than in the later stages. Protein, oil and starch contents increased gradually from day 7 to day 42. The rate of accumulation of oil was found to be at the highest level between 21–28 days after flowering, while the rate of protein deposition was greatest between days 35–42. Inditiation of seed maturation seems to start 21 days after flowering in okra seeds.