Cereal Foods Research Articles

Leaf Damage Based Phenotyping Technique and Its Validation Against Fall Armyworm, Spodoptera frugiperda (J. E. Smith), in Maize.

Globally, maize is an important cereal food crop with the highest production and productivity. Among the biotic constraints that limit the productivity of maize, the recent invasion of fall armyworm (FAW) in India is a concern. The first line of strategy available for FAW management is to evaluate and exploit resistant genotypes for inclusion in an IPM schedule. Screening for resistant maize genotypes against FAW is in its infancy in India, considering its recent occurrence in the country. The present work attempts to optimize screening techniques suited to Indian conditions, which involve the description of leaf damage rating (LDR) by comparing injury levels among maize genotypes and to validate the result obtained from the optimized screening technique by identification of lines potentially resistant to FAW under artificial infestation. Exposure to 20 neonate FAW larvae at the V5 phenological stage coupled with the adoption of LDR on a 1–9 scale aided in preliminary characterize maize genotypes as potentially resistant, moderately resistant, and susceptible. The LDR varies with genotype, neonate counts, and days after infestation. The genotypes, viz., DMRE 63, DML-163-1, CML 71, CML 141, CML 337, CML 346, and wild ancestor Zea mays ssp. parviglumis recorded lower LDR ratings against FAW and can be exploited for resistance breeding in maize.

The Fate of IgE Epitopes and Coeliac Toxic Motifs during Simulated Gastrointestinal Digestion of Pizza Base.

Understanding how food processing may modify allergen bioaccessibility and the evolution of immunologically active peptides in the gastrointestinal tract is essential if knowledge-based approaches to reducing the allergenicity of food are to be realised. A soy-enriched wheat-based pizza base was subjected to in vitro oral–gastro–duodenal digestion and resulting digests analysed using a combination of sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and mass spectrometry (MS). The digestion profile of pizza base resembled that of bread crust where higher temperatures during baking reduced protein solubility but still resulted in the generation of a complex mixture of peptides. MS profiling showed numerous peptides carrying IgE epitopes, and coeliac toxic motifs were in excess of 20–30 residues long and were only released after either 120 min of gastric digestion or a combination of gastric and duodenal digestion. In silico prediction tools showed an overestimated number of cleavage sites identified experimentally, with low levels of atypical peptic and chymotryptic cleavage sites identified particularly at glutamine residues. These data suggest that such alternative pepsin cleavage sites may play a role in digestion of glutamine-rich cereal foods. They also contribute to efforts to provide benchmarks for mapping in vitro digestion products of novel proteins which form part of the allergenicity risk assessment.

Automatic Rice Disease Detection and Assistance Framework Using Deep Learning and a Chatbot

Agriculture not only supplies food but is also a source of income for a vast population of the world. Paddy plants usually produce a brown-coloured husk on the top and their seed, after de-husking and processing, yields edible rice which is a major cereal food crop and staple food, and therefore, becomes the cornerstone of the food security for half the world’s people. However, with the increase in climate change and global warming, the quality and its production are highly degraded by the common diseases posed in rice plants due to bacteria and fungi (such as sheath rot, leaf blast, leaf smut, brown spot, and bacterial blight). Therefore, to accurately identify these diseases at an early stage, recently, recognition and classification of crop diseases is in burning demand. Hence, the present work proposes an automatic system in the form of a smartphone application (E-crop doctor) to detect diseases from paddy leaves which can also suggest pesticides to farmers. The application also has a chatbot named “docCrop” which provides 24 × 7 support to the farmers. The efficiency of the two most popular object detection algorithms (YOLOv3 tiny and YOLOv4 tiny) for smartphone applications was analysed for the detection of three diseases—brown spot, leaf blast, and hispa. The results reveal that YOLOv4 tiny achieved a mAP of 97.36% which is significantly higher by a margin of 17.59% than YOLOv3 tiny. Hence, YOLOv4 tiny is deployed for the development of the mobile application for use.

Indian Wheat Genomics Initiative for Harnessing the Potential of Wheat Germplasm Resources for Breeding Disease-Resistant, Nutrient-Dense, and Climate-Resilient Cultivars.

Wheat is one of the major staple cereal food crops in India. However, most of the wheat-growing areas experience several biotic and abiotic stresses, resulting in poor quality grains and reduced yield. To ensure food security for the growing population in India, there is a compelling need to explore the untapped genetic diversity available in gene banks for the development of stress-resistant/tolerant cultivars. The improvement of any crop lies in exploring and harnessing the genetic diversity available in its genetic resources in the form of cultivated varieties, landraces, wild relatives, and related genera. A huge collection of wheat genetic resources is conserved in various gene banks across the globe. Molecular and phenotypic characterization followed by documentation of conserved genetic resources is a prerequisite for germplasm utilization in crop improvement. The National Genebank of India has an extensive and diverse collection of wheat germplasm, comprising Indian wheat landraces, primitive cultivars, breeding lines, and collection from other countries. The conserved germplasm can contribute immensely to the development of wheat cultivars with high levels of biotic and abiotic stress tolerance. Breeding wheat varieties that can give high yields under different stress environments has not made much headway due to high genotypes and environmental interaction, non-availability of truly resistant/tolerant germplasm, and non-availability of reliable markers linked with the QTL having a significant impact on resistance/tolerance. The development of new breeding technologies like genomic selection (GS), which takes into account the G × E interaction, will facilitate crop improvement through enhanced climate resilience, by combining biotic and abiotic stress resistance/tolerance and maximizing yield potential. In this review article, we have summarized different constraints being faced by Indian wheat-breeding programs, challenges in addressing biotic and abiotic stresses, and improving quality and nutrition. Efforts have been made to highlight the wealth of Indian wheat genetic resources available in our National Genebank and their evaluation for the identification of trait-specific germplasm. Promising genotypes to develop varieties of important targeted traits and the development of different genomics resources have also been highlighted.

African cereal fermentations: A review on fermentation processes and microbial composition of non-alcoholic fermented cereal foods and beverages

Africa has a rich tradition of cereal fermentations to produce diverse products including baked goods, porridges, non-alcoholic beverages and alcoholic beverages. Diversity also relates to the choice of the fermentation substrates, which include wheat, maize, teff, sorghum and millet, and the fermentation processes that are used in food production. For fermentation processes that are used in baking and brewing, it is well established that the composition of fermentation microbiota and thus the impact of fermentation on product quality is determined by the choice of fermentation conditions. This link has not been systematically explored for African cereal fermentations. This review therefore aims to provide an overview on the diversity of African fermented cereal products, and to interrogate currently available literature data with respect to the impact of fermentation substrate and fermentation processes on the assembly of fermentation microorganisms and product quality.

Extrusion Simulation for the Design of Cereal and Legume Foods.

A 1D global twin-screw extrusion model, implemented in numerical software, Ludovic®, was applied to predict extrusion variables and, therefore, to design various starchy products with targeted structure and properties. An experimental database was built with seven starchy food formulations for manufacturing dense and expanded foods made from starches, starch blends, breakfast cereals, pulse crop ingredients such as pea flour, fava bean flour, and fava bean starch concentrated, and wheat flour enriched with wheat bran. This database includes the thermal and physical properties of the formulations at solid and molten states, melt viscosity model, extruder configurations and operating parameters, and extruded foods properties. Using extrusion and viscosity models, melt temperature (T) and specific mechanical energy (SME) were satisfactorily predicted. A sensitivity analysis of variables at die exit was performed on formulation, extruder configuration, and operating parameters, generating the extruder operating charts. Results allowed the establishment of relationships between predicted variables (T, SME, melt viscosity) and product features such as starch and protein structural change, density and cellular structure, and functional properties. The extrusion operating conditions leading to targeted food properties can be assessed from these relationships and also the relationship between extrusion operating parameters and variables provided by simulation.

Estimation of Iron Availability in Modified Cereal β-Glucan Extracts by an in vitro Digestion Model.

For cereal-based foods rich in dietary fibers, iron bioavailability is known to be poor. For native cereal β-glucan extracts, literature has demonstrated that the main factor impacting the bioavailability is phytic acid, which is often found in association with dietary fibers. During food processing, β-glucan can undergo modifications which could potentially affect the equilibrium between phytic acid, fiber, and iron. In this study, an in vitro digestion was used to elucidate the iron dialysability, and hence estimate iron availability, in the presence of native, chelating resin (Chelex)-treated, oxidised, or partially hydrolysed oat and barley β-glucan extracts (at 1% actual β-glucan concentration), with or without phytase treatment. It was confirmed that pure, phytic acid-free β-glucan polysaccharide does not impede iron availability in cereal foods, while phytic acid, and to a smaller extent, also proteins, associated to β-glucan can do so. Neither Chelex-treatment nor partial hydrolysis, 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) or NaIO4 oxidation significantly influenced the phytic acid content of the β-glucan extracts (ranging 2.0–3.9%; p > 0.05). Consequently, as long as intrinsic phytic acid was still present, the β-glucan extracts blocked the iron availability regardless of source (oat, barley) or Chelex-treatment, partial hydrolysis or NaIO4-oxidation down to 0–8% (relative to the reference without β-glucan extract). Remarkably, TEMPO-oxidation released around 50% of the sequestered iron despite unchanged phytic acid levels in the modified extract. We propose an iron-mobilising effect of the TEMPO product β-polyglucuronan from insoluble Fe(II)/phytate/protein aggregates to soluble Fe(II)/bile salt units that can cross the dialysis membrane. In addition, Chelex-treatment was identified as prerequisite for phytase to dramatically diminish iron retention of the extract for virtually full availability, with implications for optimal iron bioavailability in cereal foods.

The regulatory effect of fermented black barley on the gut microbiota and metabolic dysbiosis in mice exposed to cigarette smoke

Smoking is a global public health event that can cause oxidative stress and gut microbiota dysbiosis and is related to the occurrence of diseases such as cancer and respiratory system disease. We previously found that fermented black barley was rich in antioxidative components such as polyphenols and flavonoids and regulated gut microbiota dysbiosis. In the present study, the protective effects of fermented black barley on cigarette smoke-induced damage, such as lung, reproduction organ injury, gut microbiota and metabolic dysbiosis, were investigated. Fermented black barley (100 μL/10 g·BW per day, containing 1 × 108 CFU/mL Lactobacillus) was administered orally to male ICR mice that were regularly exposed to cigarette smoke (one time a day, 15 cigarettes each time, 30 min/time). The intervention lasted continuously for 12 weeks. The results showed that compared to the group exposed only to cigarette smoke, fermented black barley treatment alleviated the pathological damage to lung and testis tissues and significantly increased the total sperm motility and antioxidative capacity of the lung. Fermented black barley also regulated the intestinal microbiome diversity; reduced the relative abundances of Lactobacillus, Turicibacter and Bifidobacterium; and increased the relative abundances of Oscillospira and Ruminococcus at the genus level. Furthermore, the metabolic profile was investigated via analysis of the abundances of fecal and hepatic metabolites, and it was shown that fermented black barley treatment alleviated the metabolic dysbiosis of lipids, amino acids, and the biosynthesis of steroid hormones (such as dehydroepiandrosterone sulfate, etc.) induced by cigarette smoking, which approached normal conditions. These regulatory effects may partially elucidate the beneficial role of fermented black barley in alleviating the harmful effects of cigarette smoking. In summary, supplementation with fermented cereal food may be a helpful way to ameliorate cigarette smoking-induced damage.

Furfurilactobacillus milii sp. nov., isolated from fermented cereal foods.

Genomic characterization of Furfurilactobacillus rossiae revealed that strains which were previously identified as F. rossiae are genetically heterogeneous. The 16S rRNA gene sequences of strains FUA3430, FUA3583, C5, FUA3115 and FUA3119, were 99.6 % identical to F. rossiae but the core genome analysis revealed that these strains share less than 93 % average nucleotide identity (ANI) with the F. rossiae type strain DSM 15814T. Because the ANI value is below the threshold for delineation of bacterial species, we propose the novel species Furfurilactobacillus milii sp. nov. with the type strain FUA3430T (=DSM 113338T=LMG 32478T). Strains of F. milii have smaller genomes than F. rossiae, lack the pdu-cbi-cob-hem cluster which is responsible for 1,2-propanediol utilization in F. rossiae, and lack genes involved in ethanolamine utilization. Two strains of the novel species (FUA3430T and FUA3583) were compared to F. rossiae FUA3214. Analysis of the cellular fatty acid composition and metabolite analysis did not reveal significant differences between F. milii sp. nov. and F. rossiae FUA3124. Although the growth requirements with respect to temperature and pH were very similar, only the strain of F. rossiae utilized melibiose and d-xylose. Morphological differences were also seen in the colony and cell size of the novel compared to F. rossiae.

Effect of Flaking and Precooking Procedures on Antioxidant Potential of Selected Ancient Cereal and Legume Flours.

Consumption of cereals (and particularly ancient cereals) is considered the base of a healthy diet, and all current dietary guidelines have cereals at the bottom of the nutrition pyramid. Together with cereals, legumes are an excellent source of nutrients and nutraceuticals. The effects of agroindustrial pretreatments (flaking and precooking processes) on the antioxidant potential of flours from ancient cereals and legumes were studied. The extraction of free hydrophilic phenolic compounds was carried out in a hydroalcoholic solvent mixture via an ultrasound-assisted process. Furthermore, the solid residue was successively hydrolyzed by an alkaline solution to extract the bound phenolic fraction. Both free and bound extracted fractions were then quantitatively characterized for total polyphenolic and flavonoid contents, and the antioxidant potential was determined by carrying out the ABTS and DPPH radical scavenging assays, expressing the results (in both cases) as the Trolox equivalent antioxidant capacity (TEAC/ABTS and TEAC/DPPH, respectively). The samples were also extracted in organic apolar solvents (acetone or water-saturated iso-butanol) to quantitatively characterize lipophilic antioxidant compounds and pigments. A discussion on the comparison of these analytical parameters of flours obtained from raw, flaked, and precooked cereals and legumes is reported revealing that (i) phenolic compounds are mainly present in the post-hydrolysis extract (bound fraction), (ii) the precooking process significantly reduced the concentration of antioxidants, (iii) the flaking process slightly increased the phenolic content, (iv) legumes were less influenced by pretreatments, suggesting the possibility of using legumes to enrich cereal foods.

Both alkyl chain length and V-amylose structure affect the structural and digestive stability of amylose-alkylresorcinols inclusion complexes

Alkylresorcinols (ARs) are a group of bioactive phenolic lipids and mostly concentrated in the bran of whole grains. In this study, the influences of alkyl chain length of ARs and V-amylose structure on the stability of V-amylose-ARs inclusion complexes were characterized. On the one hand, X-ray diffraction (XRD), differential scanning calorimetry (DSC), and in vitro digestion studies of complexes showed that the crystallinity, thermo-stability, and digestion resistance of V-amylose-ARs inclusion complexes increased with increasing alkyl chain length of ARs. On the other hand, V6-amylose-ARs inclusion complexes displayed the strongest thermostability, the highest crystallinity, and the lowest digestibility compared to V7-amylose-ARs inclusion complexes and V8-amylose-ARs inclusion complexes. It could be concluded that both the helical structure of hydrated V6-amylose and ARs with longer alkyl chain stabilized the structure and stability of the inclusion complexes. This work could pave a way to develop bioactive cereal foods with high bioaccessibility of ARs.

Main complementary food ingredients contributing to aflatoxin exposure to infants and young children in Kongwa, Tanzania

Complementary foods (CFs) provided to infants and young children (IYC) in sub-Saharan Africa contain ingredients that are susceptible to aflatoxin contamination. Chronic dietary exposure to aflatoxins is associated with health consequences. This study assessed the risk of exposure of IYC (6-12-month-old) in Kongwa, Tanzania to aflatoxins through CFs. The intake of aflatoxin susceptible flours (ingredients) in CFs by 35 IYC was estimated through multiple-pass 24-hr dietary recalls. Samples of the ingredients were tested for aflatoxins using High-Performance Liquid Chromatography. Exposure of a child to aflatoxins was estimated by a deterministic approach. The contribution of an ingredient to the overall exposure was estimated statistically. The key ingredients of CFs consumed by the IYC were maize, sorghum, pearl millet, rice, and groundnuts (pre-or post-blended with the other ingredients). Cereal and groundnut-based CFs were given as thin or stiff porridge. The average per capita daily intake of CFs was 89.45 g. About 82.14% of the CF ingredients were contaminated with aflatoxin B1 (AFB1) in the range of 0.27–317 μg/kg, with a median of 3.96 μg/kg. AFB1 exposures ranged from 0.33 to 1168 ng/kg bw/day (median of 23.08 ng/kg bw/day). The Margins of Exposure were less than 10,000 for all the IYC, signifying a public health concern. Post-blended groundnut flour, followed by maize, contributed the most to the exposure of IYC to AFB1. Groundnut and maize used as CFs in Kongwa are likely to be the main contributors to the exposure of IYC to AFB1. Caregivers should be advised to replace maize and groundnuts with well-processed less susceptible cereals like pearl millet and other legumes, respectively. • Tanzanian infant and young children (IYC) are at high risk of exposure to aflatoxins. • Aflatoxins are common fungi contaminants in cereal and groundnut-based foods. • Maize and groundnuts contribute the most to aflatoxin exposures of IYC in Tanzania. • Alternative foods may minimize the risk of aflatoxin exposure in Tanzanian IYC.

Residual Effect of Phosphorus on Grain Yield of Maize in Pawe District of North Western Ethiopia

Phosphorus is an important nutrient element in crop productivity. Maize is one of the common stable food cereal crop grown in different parts of Ethiopia and mostly affected by phosphorous nutrient. An experiment was conducted to evaluate the effects of different levels of residual P for three consecutive years (0, 20, 40, and 80 kg ha -1 ) in Pawe agricultural research center. At the fourth year by applying 0, 10, 20, and 30 kg ha -1 of P final experiment was conducted. the highest grain yield 8359 kg/ha was recorded from the interaction R12P3 which means a residual of 0, 40, 20, 20 kg P/ha for four consecutive years and 20 kg/ha at the experimental year. Over application of P from the previous seasons significantly affects the yield of maize in the experiment year regardless of the current dosage. So the experiment indicates that over accumulation of P affects the growth and yield of maize. DOI: 10.7176/JBAH/12-9-03 Publication date: May 31 st 2022

A Cross-Sectional Audit of Sorghum in Selected Cereal Food Products in Australian Supermarkets.

Sorghum (Sorghum bicolor (L.) Moench) may play a role in mechanisms that elicit favourable health effects. In Australia, sorghum is successfully grown, but it is not widely consumed, and its presence in common food products is unknown. This study examined the utilisation of sorghum in common food products, specifically breakfast cereals and snack bars, in a cross-sectional study of five supermarkets in New South Wales, over a 7-day period in February 2020. Details relating to ingredients, food format, brand, and product name were recorded. Sorghum was present in 6.1% (23/379) of breakfast cereals in a variety of formats, such as extruded shapes, flour, and puffed grain. In 8.7% of these, sorghum was listed as the first ingredient (greatest contribution by weight). Sorghum was utilised in 2% (6/298) of snack bars mainly as puffed sorghum and was listed in the fourth or subsequent position in the ingredient lists for all. ‘Sorghum’ did not appear in the name of any products. In conclusion, this baseline study indicates that sorghum is present in a small proportion of breakfast cereals and snack bars, highlighting the opportunity for greater investment in sorghum food innovation and marketing that would encourage consumer recognition and expand the product range.

The Protein Losses of Three Major Cereal Crops by Natural Disasters in China From 1988 to 2020

Natural disasters have a major detrimental impact on agricultural production. In recent decades, China has experienced more frequent natural disasters as a result of climate change. Although the spatial and temporal changes in natural disasters for individual catastrophic activities are well understood, the impact of several disasters on cereal crop productivity and subsequent quality loss remains unknown. Furthermore, due to the key significance of cereal in China’s daily diet, a decrease in cereal quality, namely protein, will have a detrimental effect on nutrient supply. To better understand the relationship between natural disasters and cereal crop food quality in China, we used province-level data from 1988 to 2020 to construct a dataset of natural disasters, crop production, and protein contents of cereal crops (rice, wheat, and maize). Our findings suggest that activities in areas affected by natural disasters have decreased dramatically since the 21st century, with changes in areas affected by such disasters varying by province. Between 1988 and 2020, the total protein losses from grain and straw harvests due to natural disasters were 11.93 and 391.27 million tons. Overall, the annual mean total protein loss in maize, rice, and wheat was 4,982.26, 5,055.4, and 4,200.34 thousand tons, respectively. Although was responsible for half of the protein losses in more than half of the provinces. Drought and floods accounted for 80% of the total area affected by all natural disasters.

A comprehensive review of wheat phytochemicals: From farm to fork and beyond.

The health benefits of whole wheat consumption can be partially attributed to wheat's phytochemicals, including phenolic acids, flavonoids, alkylresorcinols, carotenoids, phytosterols, tocopherols, and tocotrienols. It is of increasing interest to produce whole wheat products that are rich in bioactive phytochemicals. This review provides the fundamentals of the chemistry, extraction, and occurrence of wheat phytochemicals and includes critical discussion of several long-lasting issues: (1) the commonly used nomenclature on distribution of wheat phenolic acids, namely, soluble-free, soluble-conjugated, and insoluble-bound phenolic acids; (2) different extraction protocols for wheat phytochemicals; and (3) the chemistry and application of in vitro antioxidant assays. This review further discusses recent advances on the effects of genotypes, environments, field management, and processing techniques including ultrafine grinding, germination, fermentation, enzymatic treatments, thermal treatments, and food processing. These results need to be interpreted with care due to varied sample preparation protocols and limitations of in vitro assays. The bioaccessibility, bioavailability, metabolism, and potential health benefits of wheat phytochemicals are also reviewed. This comprehensive and critical review will benefit scientific researchers in the field of bioactive compounds of cereal grains and also those in the cereal food industry to produce high-quality functional foods.

Diets with Higher Vegetable Intake and Lower Environmental Impact: Evidence from a Large Australian Population Health Survey.

Increasing the consumption of vegetables is a public health nutrition priority in Australia. This must be achieved in the context of lowering dietary environmental impacts. In this study, a subgroup of 1700 Australian adult daily diets having a higher diet-quality score and a lower environmental impact score was isolated from Australian Health Survey data. These diets were primarily distinguished by their lower content of energy-dense/nutrient-poor discretionary foods. Among these diets, those with higher levels of vegetable intake were characterized by greater variety of vegetables eaten, lower intake of bread and cereal foods, and higher intake of red meat. These diets also had a greater likelihood of achieving recommended intakes for a range of vitamins and minerals. These findings highlighted the importance of considering the total diet in developing strategies to promote healthy and sustainable food consumption, as well as the need to understand the interrelationships between foods that exist in a local cultural context. As vegetables are usually eaten with other foods, higher vegetable consumption in Australia could be supported by encouraging more regular consumption of the types of meals that include larger quantities of vegetables. Our results showed that this was possible while also substantially lowering total dietary environmental impacts.

Diet communication on the early Silk Road in ancient China: multi-analytical analysis of food remains from the Changle Cemetery

Characterization of ancient food remains could reflect how people exploited biological resources and interacted with different cultures in antiquity. In this study, Fourier Transform Infrared Spectroscopy (FTIR), starch grain, phytolith, stable isotope analysis and proteomics were adopted to characterize the composition of the food remains including three cereal foodstuffs, some meat strips and a kebab discovered at the Changle Cemetery (202 BCE–220 CE), Ningxia, northwest China, a key area on the Silk Road. The results show that the cereal foods were baked cakes, primarily made from foxtail millet (Setaria italica). One cake was simply made of millet grains, the others were more elaborately comprised of millet flour with the addition of barley flour and meat from cattle (Bos taurus) and chicken (Gallus gallus). These findings indicate that grinding and baking technologies, which were considered as the culinary tradition in western Eurasia, had been adopted at the latest by the inhabitants in Ningxia region at that time. The large-scale migration from central China to Ningxia and the opening up of the Silk Road during the Han Dynasty gave rise to the diet communication and assimilation in this border area. Moreover, the meat strips were identified as dried beef, and the kebab was likely to be made from sheep/goat meat, wherein the latter is the earliest scientific evidence of mutton kebab in ancient China up to our knowledge. The analytical strategy could be widely applied in characterizing ancient visible food remains in order to better understand their preparation methods.

Heat Tolerance and Effect of High Temperature on Floral Biology and Physiological Parameters in Rice: A Review

Rice (Oryza sativa L.) is one of the major cereal staple food crops consumed by more than 50 per cent of the world’s population. Due to global climatic changes, the crop has to withstand higher temperatures in the near future. In India, rice cultivation is more affected by climate change and it contributes to yield loss and in severe cases results in crop failure both of which leads to economic losses. Grain yield declined by 10% for each 1oC increase in minimum temperature in the dry season whereas the effect of maximum temperature was insignificant. Significant variation exists among rice germplasm in response to high temperature stress. Producing an economically significant yield under heat stress conditions depends on floral biology of rice and several plant physiological parameters and mechanisms that contribute to heat tolerance in the field, such as photosynthesis, chlorophyll content, canopy temperature depression and concomitant increases of transcripts coding for proteins involved in protection. According to the objectives of this study, the literature pertaining to the aspects of heat tolerance and effect of high temperature on floral biology and physiological parameters in rice is briefly reviewed.

Identifying Quality Protein Maize Inbred Lines for Improved Nutritional Value of Maize in Southern Africa.

Malnutrition, as a result of deficiency in essential nutrients in cereal food products and consumption of a poorly balanced diet, is a major challenge facing millions of people in developing countries. However, developing maize inbred lines that are high yielding with enhanced nutritional traits for hybrid development remains a challenge. This study evaluated 40 inbred lines: 26 quality protein maize (QPM) lines, nine non-QPM lines, and five checks (three QPM lines and two non-QPM lines) in four optimum environments in Zimbabwe and South Africa. The objective of the study was to identify good-quality QPM inbred lines for future hybrid breeding efforts in order to increase the nutritional value of maize. The QPM lines had a lower protein content (7% lower) than that of the non-QPM lines but had 1.9 times more tryptophan and double the quality index. The lysine- and tryptophan-poor α-zein protein fraction was 41% lower in QPM than in non-QPM, with a subsequent increase in γ-zein. There was significant variation within the QPM inbred lines for all measured quality characteristics, indicating that the best lines can be selected from this material without a yield penalty. QPM lines that had both high protein and tryptophan levels, which can be used as parents for highly nutritious hybrids, were identified.