Altafhusain Nadaf

Characterisation of aromatic rice (Oryza sativa L.) germplasm and correlation between their agronomic and quality traits

Eighty-eight aromatic cultivars collected from Maharashtra state were assessed for determinants of kernel quality (kernel size-shape, test weight and aroma) and grain morphology such as awning, lemma and palea characters, pubescence, colour of sterile lemma and apiculus colour. We, report seven cultivars—‘Girga’, ‘Kothmirsal’, ‘Kala bhat’, ‘Chimansal’, ‘Jiri’, ‘Kalsal’ ‘Velchi’ and ‘Kali kumud’ as indigenous to southern India. Of the 69 cultivars characterized for agronomic traits 36 cultivars were exquisite genotypes and possessed one or more superior traits such as early flowering, dwarf stature, higher number of productive tiller per plant; long panicles; higher number of filled grains per panicle and strong aroma. Variability in aromatic cultivars was assessed on the basis of nine traits placed aromatic rice cultivars in five clusters. Number of cultivars in each cluster ranged from 1 to 33. 27 significant correlations were obtained in the physical, agronomic and grain morphology traits. Aroma was found to be negatively associated with days to 50% flowering as well as with filled grains per panicle. However, correlation between panicle length and effective tillers with aroma was not observed. Therefore, to increase the yield, improvement in length of panicle and increasing number of productive tillers in medium or mild scented cultivars would be the best strategy.

A new endemic species of Pandanaceae from India: Pandanus palakkadensis

SummaryPandanus palakkadensis, a new species from the Palakkad, Kerala state, India is described and illustrated. The new species can be easily distinguished from the other members of the genus it most closely resembles, P. canaranus Warb. and P. furcatus Roxb. in having a drupe with flat pileus, endocarp broadly truncate, concave on either side with distinctly elevated shoulders, a sharp, obliquely pointed stigma and cylindrical fruit. This distinctive species is endemic to the region of collection and is classified as Critically Endangered (CR) based on the IUCN Red List criteria.

Thirty-three years of 2-acetyl-1-pyrroline, a principal basmati aroma compound in scented rice (Oryza sativa L.): a status review.

Rice is the staple food of around 3 billion people, most of them in Asia which accounts for 90% of global rice consumption. Aromatic rices have been preferred over non-aromatic rice for hundreds of years. They have a premium value in national as well as international market owing to their unique aroma and quality. Many researchers were involved in identifying the compound responsible for the pleasant aroma in aromatic rice in the 20th century. However, due to its unstable nature, 2-acetyl-1-pyrroline (2AP) was discovered very late, in 1982. Buttery and co-workers found 2AP to be the principal compound imparting the pleasant aroma to basmati and other scented rice varieties. Since then, 2AP has been identified in all fragrant rice (Oryza sativa L.) varieties and a wide range of plants, animals, fungi, bacteria and various food products. The present article reviews in detail biochemical and genetic aspects of 2AP in living systems. The site of synthesis, site of storage and stability in plant systems in vivo is of interest. This compound requires more research on stability to facilitate use as a food additive.

2-Acetyl-1-pyrroline augmentation in scented indica rice (Oryza sativa L.) varieties through Δ(1)-pyrroline-5-carboxylate synthetase (P5CS) gene transformation.

Abstract2-Acetyl-1-pyrroline (2AP) has been identified as a principal aroma compound in scented rice varieties. Δ1-Pyrroline-5-carboxylate synthetase (P5CS) gene is reported to regulate the proline synthesis in plants and acts as the precursor of 2AP. Two scented indica rice varieties, namely Ambemohar 157 and Indrayani, were subjected to Agrobacterium tumefaciens-mediated genetic transformation containing P5CS gene. Overexpression of P5CS led to a significant increase in proline, P5CS enzyme activity and 2AP levels in transgenic calli, vegetative plant parts, and seeds over control in both the varieties. 2AP level increased more than twofold in transgenic seeds in both varieties. This is the first report of enhancement in 2AP content through overexpression of using P5CS gene, indicating the role of proline as a precursor amino acid in the biosynthesis of 2AP in scented rice.

Aroma volatile analyses and 2AP characterization at various developmental stages in Basmati and Non-Basmati scented rice (Oryza sativa L.) cultivars

BackgroundRice plant growth is comprised of distinct phases, such as vegetative, reproductive, grain filling and maturity phases. In these phases synthesis and availability of primary and secondary metabolites including volatile organic compounds (VOC’s) is highly variable. In scented rice, aroma volatiles are synthesized in aerial plant parts and deposited in mature grains. There are more than 100 VOCs reported to be responsible for flavor in basmati rice. It will be interesting to keep track of aroma volatiles across the developmental stages in scented rice. Therefore, the aroma volatiles contributing in aroma with special reference to the major compound 2 acetyl-1-pyrroline (2AP) were screened at seven developmental stages in scented rice cultivars Basmati-370 and Ambemohar-157 along with non-scented rice cultivar IR-64 as a control following HS-SPME-GC-MS method. In addition, the expression levels of key genes and precursor levels involved in 2AP biosynthesis were studied.ResultsThe study indicated that volatilome of scented rice cultivars is more complex than non-scented rice cultivar. N-heterocyclic class was the major distinguishing class between scented from non-scented rice. A total of 14 compounds including, 2AP were detected specifically in scented rice cultivars. Maximum number of compounds were synthesized at seedling stage and decreased gradually at reproductive and maturity. The seedling stage is an active phase of development where maximum number green leaf volatiles were synthesized which are known to act as defense molecules for protection of young plant parts. Among the 14 odor active compounds (OACs), 10 OACs were accumulated at higher concentrations significantly in scented rice cultivars and contribute in the aroma. 2AP content was highest in mature grains followed by at booting stage. Gene expression analysis revealed that reduced expression of betaine aldehyde dehydrogenase 2 (badh2) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and elevated level of triose phosphate isomerase (TPI) and Δ1-Pyrolline-5-carboxylic acid synthetase (P5CS) transcript enhances 2AP accumulation.ConclusionsMost diverse compounds were synthesized at seedling stage and OACs were accumulated more at flowering followed by seedling stage. Distinct accumulation pattern exists for 2AP and other aroma volatiles at various developmental stages. The study revealed the mechanism of 2AP accumulation such that 2AP in mature grains might be transported from leaves and stem sheath and accumulation takes place in grains.

33 Years of 2‐Acetyl‐1‐Pyrroline, a Principle Basmati Aroma Compound in Scented Rice (Oryza sativa L.): A Status Review

Rice is the staple food of around 3 billion people, most of them in Asia which accounts for 90% of global rice consumption. Aromatic rices have been preferred over non-aromatic rice for hundreds of years. They have a premium value in national as well as international market owing to their unique aroma and quality. Many researchers were involved in identifying the compound responsible for the pleasant aroma in aromatic rice in the 20th century. However, due to its unstable nature, 2-acetyl-1-pyrroline (2AP) was discovered very late, in 1982. Buttery and co-workers found 2AP to be the principal compound imparting the pleasant aroma to basmati and other scented rice varieties. Since then, 2AP has been identified in all fragrant rice (Oryza sativa L.) varieties and a wide range of plants, animals, fungi, bacteria and various food products. The present article reviews in detail biochemical and genetic aspects of 2AP in living systems. The site of synthesis, site of storage and stability in plant systems in vivo is of interest. This compound requires more research on stability to facilitate use as a food additive.

Diversity analysis in selected non-basmati scented rice collection.

Diversity analysis among 23 rice varieties including 16 non-basmati scented accessions, 5 basmati accessions and 2 non-scented accessions was performed by random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) marker systems. The varieties analyzed by 11 RAPD and 8 ISSR primers yielded an average of 65% and 80% polymorphism, respectively. The average number of polymorphic bands generated per RAPD primer was 6 and per ISSR primer was 5.87. RAPD and ISSR data analysis individually could not segregate basmati and non-basmati scented rice accessions. However, the analysis using a combined data could group basmati and non-basmati scented rice accessions separately. The bands present specifically among three accessions of non-basmati scented rice were also identified. The study revealed a high genetic diversity among non-basmati scented rice accessions.

Pandanus amaryllifolius Roxb. cultivated as a spice in coastal regions of India.

Pandanus amaryllifolius, an herb, is cultivated in home gardens in coastal regions of India. The leaves are added to ordinary rice while cooking to impart basmati rice aroma. The plant bears the same aroma principle 2-acetyl-1-pyrroline (2AP) that has been reported in Basmati and other scented rice. Quantitatively the 2AP contents are highest in this plant among the plant kingdom. Therefore, it has good scope for commercial cultivation.

Pandanus mangalorensis: a new species of Pandanaceae from Southern India

SummaryPandanus mangalorensis, a new species from the Mangalore district, Karnataka state, India is described and illustrated. The new species differs from other Pandanus species in having prominent multiple branching, triangular infructescence, drupes arranged on a bony triangular ring, drupe apex pyramidal with acute and bifid style and stigma and central projection extended up to style base. The species appears to be endemic to the collection site and is assigned as Critically Endangered (CR) based on IUCN Red List Categories and Criteria.

Genome editing for targeted improvement of plants

Recent advances in gene/genome editing technologies, such as engineered meganucleases (EMNs), zinc finger nucleases (ZFNs), transcription activator-like effector nuclease (TALENs) and clustered regularly interspaced palindromic repeats (CRISPR/Cas9) allowed researchers to precisely modify or mutate genes. These genome editing tools make double-strand breaks (DSB) in DNA and then repair it by employing error-prone non-homologous end joining (NHEJ) or homology directed repair (HDR) mechanism which leads to mutation in specific location in genome. Since these editing techniques are simple to use, highly efficient and specific as compared to earlier mutation methods, their use in plant biology research is increasing rapidly to enhance biotic and abiotic stress tolerance, increased nutritional value and new trait development. Here, we review the applications of EMNs, ZFNs, TALENs and CRISPR/Cas9 in various plants (cereals, vegetable, oil crops and fruits), comparison of genome editing methods and their biosafety regulations.