Search

During post-rainy and rice fallow cropping seasons, popular blackgram varieties are severely affected by powdery mildew leading to severe yield loss. The lack of natural genetic variability for powdery mildew resistance in blackgram germplasm warrants mutation breeding. Hence, in this study, blackgram cultivar CO6 was mutagenized with gamma ray and ethyl methanesulphonate (EMS) to create variability for powdery mildew resistance. Seeds of blackgram CO6 were irradiated with three doses of gamma ray (200 Gy, 300 Gy and 400 Gy) followed by two doses of ethyl methanesulphonate (EMS; 20 and 30 mM) to achieve six combination treatments. Selected resistant mutants of M2 generation were characterized for agronomic, histological, enzyme and biochemical traits along with powdery mildew resistant LBG 17 and susceptible CO6 checks. Molecular variability was studied using 72 simple sequence repeat (SSR) markers. In the M2 generation, 60 powdery mildew resistant mutants were identified and a total of 25 high yielding mutants were evaluated further to confirm powdery mildew resistance and yield. Nine resistant mutants (PM 13, PM 20, PM 21, PM 42, PM 53, PM 54, PM 56, PM 57 and PM 60) and the resistant check (LBG17) showed significantly higher values for leaf density, trichome density, SOD, CAT, POX, PPO, total phenols, phytic acid and silica content. SSR markers viz., CEDG154, CEDG290, CEDG139, CEDG259, CEDG191, CEDG024, CEDG 282, CEDG 166, CEDG 232 and CEDG 088 were found polymorphic between resistant mutants and the parent CO6. The study has demonstrated that sufficient variability was induced in the blackgram for powdery mildew resistance. The elevated levels of SOD, CAT, POX, PPO, total phenols, phytic acid, and silica content observed in selected mutants may be attributed to powdery mildew resistance. The superior mutants identified in this study may be used as donors for the development of powdery mildew resistant lines or released as a new variety.

Native bees play a vital role in the pollination of different flora in an ecosystem. But the natural history of most native bee species is unknown, and knowledge about natural history helps in understanding their social evolution, and further protecting and conserving the bee species. Braunsapis mixta (Smith) is a common stem-nesting bee and a widespread endemic species of Southern Asia. This study aimed to record the nesting biology, development and natural enemies of B. mixta, which is an important pollinator of cashew. Nests of B. mixta were found in the dried sticks and pruned cut ends of cashew stems. A total of 442 nests were collected, of which 64% of the active nests were single-adult nests and 20% were of two adults. Eggs were found at the interior end, followed by larvae at varied developmental stages and pupae. The maximum number of nest occupants in a nest was 41, in which four were adults and a maximum of 11 adults were recorded in a single nest. The maximum number of females found in a nest was nine. A significant positive correlation was obtained between the number of adults and their immature stages. Egg production and brood maturation occurred throughout the year. The mean incubation period of eggs was 5.32 days. Rearing of larvae could not be achieved in the laboratory. The pupal period lasted for 11���14 days. The parasitoids recorded on B. mixta include Neochalcis breviceps and Diomorus nr. indicus.

For long term storage of seed, cryo-storage at -196°C is an effective approach among the ex-situ conservation methods. Even though the bitter gourd (Momordica charantia L.) seed has been classified as orthodox, various previous studies reported its sensitivity to sub-zero temperature. Hence, the present study was carried out to investigate the seed germination behavior of bitter gourd seeds after cryo-treatment with a view to test the cryofitness of the seeds. Results of seed viability experiments conducted in four germplasm lines such as Arka Harit, Co 1, Preethi and Bitter gourd long indicated significant differences in germination percentage in all the bitter gourd lines except Arka Harit.

Fall Armyworm (FAW), Spodoptera frugiperda, is a polyphagous pest capable of feeding over 80 plant species and was indigenous to Western Hemisphere until recently. Within a span of four years, FAW has established itself throughout most of the regions in Africa and Asia incurring significant losses in maize production. Owing to its revamped distribution range, it would be prudent to analyse the ensuing genetic changes and study the emerging phylogeographic patterns across the world. In this regard, we would like to provide a current snapshot of genetic diversity of FAW in India after two years of the initial introduction and compare it with the worldwide diversity in order to trace the origins and evolutionary trajectories of FAW in India.We have investigated around 145 FAW samples from different regions in India for strain identity and polymorphism analysis on the basis of partial mitochondrial cytochrome oxidase I (COI) gene sequences. Apart from the ancestral rice and corn strain haplotype, our study demonstrates the presence of 19 more haplotypes unique to India at a haplotype diversity of 0.498. We were also able to record the occurrence of inter-strain hybrid haplotypes of rice and corn strain in India. Regional heterogeneity within Indian populations seems to be quite low representative of extensive migration of FAW within India. Distribution analysis of pairwise differences and rejection of neutrality tests suggest that the FAW population in India is undergoing expansion. However, the scenario is much different for rest of the invaded regions like Africa and other Asian countries where FAW still appear to evolve neutrally. Our data is consistent with the findings suggesting a recent and common origin for invasive FAW populations in Asia and Africa, with significant population structure observed in Indian populations.This study reports the highest genetic diversity for Indian FAW populations till date and identifies India as the emerging hotspot for expansion of COIA rice haplotypes across the world. The findings will be useful to track the subsequent evolution of FAW and would have important ramifications for FAW behaviour and composition throughout the world.

Rice is the most important cereal that serves as the carbohydrate resource for more than one-third of the world population. To keep pace with the population growth, the productivity level should be further increased. Among the various approaches available for breaking the yield ceiling, seedling vigor plays a very significant role since, it has a direct bearing on yield and other growth parameters. High seedling vigor paves way for raising the crop by direct seeding under water stressed situations as it suppresses weeds growth due to earlier establishment and speedy growth. The present study involves characterization of 210 rice germplasm accessions with wide genetic and geographic origin for seedling vigor and its related traits under controlled environmental condition. About 32 germplasm accessions were identified as highly vigorous based on seedling vigor indices.

Knowledge about the gut bacterial communities associated with insects is essential to understand their roles in the physiology of the host. In the present study, the gut bacterial communities of a laboratory-reared insecticide-susceptible (IS), and a field-collected insecticide-resistant (IR) population of a major rice pest, the brown planthopper Nilaparvata lugens, were evaluated. The deep-sequencing analysis of the V3 hypervariable region of the 16S rRNA gene was performed using Illumina and the sequence data were processed using QIIME. The toxicological bioassays showed that compared with the IS population, IR population exhibited 7.9-, 6.7-, 14.8-, and 18.7-fold resistance to acephate, imidacloprid, thiamethoxam, and buprofezin, respectively. The analysis of the alpha diversity indicated a higher bacterial diversity and richness associated with the IR population. The dominant phylum in the IS population was Proteobacteria (99.86%), whereas the IR population consisted of Firmicutes (46.06%), followed by Bacteroidetes (30.8%) and Proteobacteria (15.49%). Morganella, Weissella, and Enterococcus were among the genera shared between the two populations and might form the core bacteria associated with N. lugens. The taxonomic-to-phenotypic mapping revealed the presence of ammonia oxidizers, nitrogen fixers, sulfur oxidizers and reducers, xylan degraders, and aromatic hydrocarbon degraders in the metagenome of N. lugens. Interestingly, the IR population was found to be enriched with bacteria involved in detoxification functions. The results obtained in this study provide a basis for future studies elucidating the roles of the gut bacteria in the insecticide resistance-associated symbiotic relationship and on the design of novel strategies for the management of N. lugens.

The broad-specificity amino acid racemase (Bsar) from Pseudomonas putida catalyzes the racemization of various amino acids, offering a flexible and feasible platform to develop a new non-antibiotic selectable marker system for plant transformation. In the present study, we demonstrated that a Bsar variant, Bsar-R174K, that is useful as a selectable marker gene in Arabidopsis and rice that were susceptible to l-lysine and D-alanine. The introduction of wild-type Bsar, Bsar-R174K or Bsar-R174A into E. coli lysine or asparagine auxotrophs was able to rescue the growth of these microorganisms in minimal media supplemented with selectable amino acid enantiomers. The transformation of Arabidopsis with Bsar or Bsar variants based on d-alanine selection revealed that Bsar-R174K had the greatest efficiency (2.40%), superior to kanamycin selection-based transformation (1.10%). Whereas, l-lysine-based selection exhibited lower efficiency for Bsar-R174K (0.17%). The progenies of selected Bsar-R174K transgenic Arabidopsis revealed normal growth properties. In addition, Bsar-R174K transgenic rice was obtained on l-lysine medium with an efficiency of 0.9%, and the progenies of the transgenic rice revealed morphologically normal phenotypes comparable with their wild-type counterparts. This study presents the first report of broad range amino acid racemase Bsar-R174K as a non-antibiotic selectable marker system applied in transgenic plants.

Pink mealybug Maconellicoccus hirsutus (Green) (Hemiptera: Pseudococcidae) is a destructive pest of agricultural and horticultural crops. Insecticides are the major tool used to control M. hirsutus. The present study was conducted to evaluate resistance to the commonly used insecticides acephate, dichlorvos, imidacloprid and buprofezin in M. hirsutus collected from seven different geographical locations of mulberry and vineyards in India. Detoxifying enzymes, namely esterase, glutathione S transferase (GST) and cytochrome P-450 (cyt-P450), were quantified in populations. One population from Erode showed a low level of resistance to acephate (resistance ratio [RR] 10.3-fold), one from Salem showed a low level of resistance to dichlorvos (resistance ratio [RR] 13.7-fold), one from Sangli showed a very low level of resistance to imidacloprid (RR 10.2-fold), and one from Chikkaballapur showed a low level of resistance to buprofezin (RR 14.8-fold). Activity ratios for detoxifying enzymes ranged from 1.8- to 4.9-fold for GST, 1.8- to 3.7-fold for esterase and 1.9- to 2.4-fold for cyt-P450. Furthermore, organophosphate resistance and activity of enzymes (esterase, GST and cyt-P450) were positively correlated. To contain the evolution of resistance to M. hirsutus infestation, buprofezin and imidacloprid could be used, supplemented with biointensive integrated management strategies and regular resistance monitoring programs.

Determining the cyanogenic potential of crop plants using traditional biochemical methods are laborious and time consuming. Presently, the Feigl-Anger paper method is being employed for qualitative analysis of cyanogenic potential of plant samples in a rapid and cost effective manner. To improve this technique from its status of qualitative to a more reliable semi-quantitative assay, the Feigl-Anger Densitometry (FAD) method was developed. This method measures the intensity of blue spots on the Feigl-Anger paper, after its exposure to HCN released from sorghum leaf tissues during a freeze thaw cycle. For colour intensity measurements, a densitometric software was employed. The densitometry results obtained from test samples and standards were compared with corresponding values obtained from quantitative spectrophotometric analysis. The results of FAD in a set of 66 germplasm lines revealed high correspondence with cyanide contents estimated through widely used spectrophotometric method of Lambert (R 2 =0.9107). Further, our method was also validated with known concentrations of KCN standards (R 2 = 0.9661). Hence it was concluded that FAD can be employed to estimate HCN content in sorghum rapidly with acceptable precision in a simple lab setup. The method can be suitable for screening of large number of mutants and segregating plant populations for the selection of low hydrogen cyanide lines in breeding programmes.

Nearly 5 000 aphid species damage crops, either by sucking plant sap or as disease-transmitting vectors. Microsatellites are used for understanding molecular diversity and eco-geographical relationships among aphid species. Expressed sequence tag (EST)-microsatellite motifs were identified through an in silico approach using inbuilt simple sequence repeat mining tools in aphid EST dataset. Microsatellite mining revealed one in every five aphid genes as containing a repeat motif, and out of 9 290 EST microsatellites mined from Aphis gossypii Glover and Acyrthosiphon pisum (Harris) (both Hemiptera: Aphididae), 80% were of A and/or T (AT, ATA, AAT, AATA, and ATTT) motifs, and the rest contained G and/or C motifs. All microsatellite sequences were annotated using BLAST. Primers for EST microsatellites were designed using the Primer 3.0 tool. 106 primer pairs of both dinucleotide repeats (DNRs) and trinucleotide repeats (TNRs), representing open reading frames (ORFs) and untranslated regions (UTRs), were synthesized to amplify 15 aphid species belonging to the subfamily Aphidinae, collected from diverse hosts. Four hundred forty-five polymorphic alleles were amplified. Fifty TNR and 23 DNR microsatellites amplified across the species studied. Polymorphism information content values of microsatellites ranged from 0.23 to 0.91, amplifying 2–16 alleles. Genetic similarity indices were estimated using the ‘NTSYS-pc’ software package. Unweighted pair group with arithmetic mean and principal component analysis resolved taxonomic relationships of the aphid species studied. The new aphid microsatellites developed will provide valuable information to researchers to study Indian aphid species diversity and genetic relationships.

Amylose content (AC) is an important parameter responsible for the cooking quality of rice. Different methods with varied principles are being employed to determine the AC on the basis of their capacity of detection. Recently, our group successfully developed a simple and rapid method for AC determination termed as cut grain dip (CGD) method. In spite of the fact that this method is proved to be user friendly, thorough validation is required for its routine application across laboratories working on rice grain quality. To verify the accuracy of the CGD method, we compared this method with routine Juliano and two pure starch-based methods namely colourimetric and high-performance size-exclusion chromatography. A total of 16 rice varieties with varied amylose contents were used for the estimation of AC using the aforementioned methods. The results indicated that the CGD method showed high correlation (r) value of 0.987 (p < 0.01) with Juliano’s method. This method also showed significant correlation values of 0.849 (p < 0.01) and 0.869 (p < 0.01) with pure starch colourimetric and high-performance size-exclusion chromatography (HPSEC) methods, respectively. While the CGD method was able to discriminate the genotypes of all the three amylose classes, the pure starch-based colourimetric method could only discriminate high and low amylose genotypes and failed to detect the intermediate class. The findings of the present investigation indicate that the CGD method is not only rapid enough to screen large germplasm samples, but it also works with acceptable accuracy for its application in rice quality breeding.

Metrocoris sikkimensis sp. nov. Type material examined: HOLOTYPE, apterous male (in 75% ethyl alcohol): INDIA, Sikkim, West Sikkim District, hill stream, Kaleg Khola, Pelling road, 27.2956°N, 88.2226°E, alt. 1841 m, 10 May 2016, coll: S. Basu. PARATYPES (in 75% ethyl alcohol):10 apterous males,10 apterous females: same data as holotype; 15 apterous males, 12 apterous females, West Sikkim District, Reshikhola River, Rinchenpong, 27.2441°N, 88.8735°E, alt. 1618 m, 9 May 2016, coll: S. Basu. 8 apterous males, 17 apterous females, INDIA: Arunachal Pradesh, West Kameng District, Rupa river, near Rupa village, Bomdila, 27.20390°N, 92.39420°E, 4804ft, 9 October, 2017, coll: S. Basu; 4 apterous males, 4 apterous females, West Kameng District, Dublekha River, Jigaon, near Rupa village, Bomdila, 27.20840°N, 92.39965°E, 4780 ft, 9 October, 2017, coll: S. Basu; 5 males, 5 females, West Kameng District, Kameng River, Nagmandir, 27.28440°N, 92.82830°E, 1495 ft, 5 October, 2017, coll: S. Basu. Description. Apterous male (Figs. 2, 4–6, 7, 9, 10, 13–17). Size: Body length 5.37, body width across mesoacetabula 2.50. Colour: Dorsally black with bright yellowish orange markings. Interocular mark on posterior margin of head distinct, yellowish (Figs. 2, 5). Eyes black. Antenna black with yellow basally. Rostrum black with yellowish laterally. Pronotum with a pair of flattened ‘u’ shaped yellowish orange markings (Figs. 2, 5). Meso- and Metanota each with a pair of yellow markings (Figs. 2, 5). Pro-, meso-and metapleura with a longitudinal yellow stripe, discontinuous near posterior margin of pronotum. Mesosternum without yellow markings. Meso- and metacetabula each with a dorsal yellow mark. Fore, mid and hind coxae and trochanters yellow. Fore femur (Fig. 7) black, yellowish basally, dorsally and ventrally. Mid and hind femora, tibiae and tarsi black. Abdominal terga I–VII and proctiger black, tergum VIII black with yellow margins (Fig. 9). Abdominal laterotergites black, except yellow posterolateral angles of last segment. Venter black, except sterna VII–IX yellowish brown (Fig. 10). Structural characteristics: Head length 0.77, width excluding eyes 0.95, narrower than pronotum. Eyes 2.2 times longer than broad, length 0.62, width 0.28. Minimum interocular width 0.63. Length of antennal segments I– IV= 2.34, 0.73, 0.79, 0.63, first segment longer than combined length of segments II–IV, without spines or bristles. Rostrum reaching to mesothorax, length 1.26. Pronotum 2.8 times wider than long, length 0.47, width 1.35, slightly bulbous. Combined length and maximum width of meso- and metanota 2.26 and 1.77 respectively. Fore femur (Fig. 7) slender, fringed with short setae, slightly constricted apically and with one or two thin small setae basally, ratio of length/width 7.51 (2.33/0.31). Fore tibia and tarsus without modification, but covered with short setae. Pretarsal claws distinct, curved and sharp. Mid and hind trochanters lacking modifications. Abdominal terga densely covered by setae, combined length 2.03, maximum width at tergum V 1.48. Abdominal sterna II–VI with golden pubescence, sterna VII–VIII long, distinctly clothed with long dense golden setae (Fig. 10). For measurements of leg segments see Table 1. Genitalia: Abdominal sternum VIII (Figs. 10, 13) short with median inverted U-shaped excavation, blunt at apex, anterior margin emarginated at middle, length 0.79, width 0.65, covered by golden setae, density increasing laterally. Pygophore (Fig. 14) elongated, broadened medially, heavily setiferous, posterior margin almost straight. Proctiger (Fig. 15) elongated, with maximum width near middle, parts of lateral margins anterior and posterior to the protrusion are concave, laterally slightly protruded near middle, apex rounded, clothed with dense setae. Parameres (Figs. 13, 17) symmetrical, projecting laterally from genital segments, curved apically, without setae, apex slightly pointed; in few individuals, parameres not visible from above. Endosomal sclerites (Fig. 16) well developed; dorsal sclerite long, entirely covering the endosomal sheath and extended apically; lateral sclerite almost straight, relatively long; ventral sclerite long. Apterous female (Figs. 3, 8, 11, 12). Size: Body length ranges from 5.10–5.39 (n=48), maximum width across mesoacetabula ranges from 2.56–2.62 (n= 48). Colour: Colour pattern similar to that of male, except yellowish marks much wider and more prominent. Structural characteristics: Head length 0.74, width (without eyes) 0.89. Length of antennal segments I–IV: 2.18, 0.79, 0.77, 0.69. Eye length 0.64, width 0.37. Minimum interocular width 0.70.Length of rostrum 1.26. Pronotum wider than long, length 0.46, width 1.51. Combined length of meso- and metanota 2.26, maximum width 2.35. Fore femur (Fig. 8) length/width ratio 8.4 (2.45/0.29), without modifications; pretarsi with sharp curved claws. Hind trochanter apically with fringe of setae. Abdominal sterna length 1.36, maximum widths 1.59 at sternum V. For measurements of leg segments see Table 2. Abdominal sternum VII (Fig. 12) more or less oval, constricted laterally, with small lobe, covered by short golden pubescence, length 0.65, width 1.09, posterior margin straight. Macropterous forms: Unknown. Etymology. The specific epithet ‘sikkimensis’ derives from its place of origin, the northeastern state of Sikkim. Discussion. The newly described species belongs to the compar group and can be easily distinguished from congeners by the entirely black venter lacking yellow markings on the meso- and metasterna (Fig. 4); the distinctive shape of male paramere (Fig. 17), which is almost straight in the middle with the apex slightly pointed and without projections; the structure of male endosomal sclerites (Fig. 16) and the male proctiger (Fig. 15); and by the female terminalia, which are ventrally more or less oval, with a small lobe and covered by golden pubescence (Fig. 12). Recently, Basu et al. (2016) reported a total of 20 species of Metrocoris from India, with a key to all known Indian species. Hence, Metrocoris sikkimensis sp. nov. is the 21 st species described from the country. Within the Metrocoris compar group, M. sikkimensis sp. nov. is closely related to M. hirtus Chen & Nieser, 1993 from China, but differs from the latter as follows. In M. hirtus, surface of the male paramere has a small projection pointing forward and the apex is blunt, whereas in M. sikkimensis sp. nov. the paramere is slightly curved apically and the apex is more or less pointed, without projections or setae. Furthermore, the male pygphore is subovate in M. hirtus, but in M. sikkimensis it is elongated and heavily setiferous and the posterior margin of male pygophore almost straight. Additionally, the male forefemur is slightly constricted apically and has one or two thin short setae basally at the ventral surface in M. sikkimensis, whereas there is no apical constriction or thin basal setae in M. hirtus. Metrocoris sikkimensis is also similar to M. nepalensis, but can be separated from the latter by the following characteristics: In M. nepalensis, the male paramere bears a small projection pointing dorsally, and by the endosoma with a small accessory apical sclerite, indistinct lateral sclerite, and long ventral sclerite. In contrast, M. sikkimensis does not have a projection on the male paramere, an accessory apical endosomal scleriteis absent, the lateral sclerite is distinct and extends upto the proximal portion of the dorsal sclerite, and the ventral sclerite is long, slender and extends forward.

Key to species of the Metrocoris compar group occurring in India 1 Mesosternum without yellow markings laterally............................................................. 2 - Mesosternum with distinct yellow markings laterally......................................................... 3 2 Male fore femur without apical constriction; paramere with blunt apex.......................... M. nepalensis Distant - Male fore femur with apical constriction (Fig.7); paramere with apex slightly pointed (Fig. 17)...... M. sikkimensis sp. nov. 3 Male fore femur without invagination near middle of posterior surface........................................... 4 - Male fore femur with a small invagination near middle of posterior surface.................................................................................................... M. darjeelingensis Basu, Polhemus & Subramanian 4 Male paramere with concave outer margin, with apex not folded laterally.... M. dinendrai Basu, Polhemus and Subramanian - Male paramere curved, forming a right angled hook, with apex folded laterally...................... M. compar (White), Published as part of Basu, Srimoyee, Chandra, Kailash & Venkatesan, Thiruvengadam, 2018, Metrocoris sikkimensis sp. nov. (Hemiptera: Heteroptera: Gerridae) from northeastern India, with a key to species of the compar group occurring in India, pp. 369-374 in Zootaxa 4471 (2) on page 374, DOI: 10.11646/zootaxa.4471.2.9, http://zenodo.org/record/1439782

Knowledge about the gut bacterial communities associated with insects is essential to understand their roles in the physiology of the host. In the present study, the gut bacterial communities of a laboratory-reared insecticide-susceptible (IS), and a field-collected insecticide-resistant (IR) population of a major rice pest, the brown planthopper

Eotrechus fuscus sp. nov. (Figs1–12) Type locality. India, Sikkim, West Sikkim District, Rimbi waterfalls. Type material. HOLOTYPE: J (apterous), INDIA: SIKKIM: West Sikkim, Rimbi waterfalls, 27.314035°N, 88.186561°E, alt. 4153 ft [= 1266 m a.s.l.], 11.v.2015, coll: S. Basu.The specimen is deposited in the National Zoological Collection of Zoological Survey of India, Kolkata (NZC-ZSI). Description. Male (apterous). Body. Body length 11.15 mm, maximum width across mesoacetabula 2.67 mm. Colour. Dorsally body colour mainly black, covered with golden pubescence. Head black, with ‘v’-shaped brown mark pointing towards posterior margin. Eyes, abdominal tergites black. Antennae and legs brown. Pronotum with a long median brown marking extending from anterior to posterior end. Meso- and metanotum black with typical dark brown markings as in Fig.1. Ventral coloration mainly black except for dark brown head, prosternum, and 8 th abdominal sternite. Structure. Head length 1.76 mm and width across eyes 1.49 mm, longer than broad, wide posteriorly. Interocular width 1.14 mm. Eyes distinct, black and ‘bean’ shaped, length 0.78 mm and width 0.51 mm. Antennae long, slender, without tubercles; length of antennal segments 1 st to 4 th (mm): 3.97: 3.39: 2.03: 2.33; first antennal segment longer than rest. Rostrum long, 3.52 mm in length, reaching beyond the forecoxa. Pronotum broader than long, length 1.44 mm and width 1.69 mm, shorter than head length and with a distinct median ridge, stretching from anterior to posterior end. Total length of meso- and metanotum 3.39 mm and width 2.29 mm, with distinct carination (Fig. 3). Fore femur (Fig. 6) slender, without any modification, slightly incrassate basally, near margin of trochanter, fringed with short hairs along exterior margin, width of fore femur 0.45 mm. Fore tarsus dark brown, covered with numerous short setae, fore claws stout and distinct. Middle and hind legs long, slender and thickened proximally. Hind femur with numerous prominent denticles on inner margin. Claws well-developed, stout and sharply bent, length of fore, middle and hind claws 0.22: 0.26: 0.27 mm. Lengths of leg segments as provided in Table 1. Abdomen long, tergites I–VIII black to dark brown, elongated. Tergites I–VII covered with short golden setae, length of abdomen 4.90 mm and width 1.77 mm. Abdominal ventrites slightly depressed from 6 th to 8 th segment, posterior margin of 7 th –8 th segment moderately emarginated in middle, covered with long, brown hairs. Segment 8 relatively long with minute notch, projecting outward near posteromedial margin. Male genitalia. Genital segments relatively large and modified, length 1.64 mm, width 0.90 mm. Proctiger (Fig. 11) distinctly bilobed, elongate, fringed with brush-like hairs, broad at both ends and with straight outer margin in middle. Dissected 8 th segment (Fig. 10) of male with round posterior margin. Pygophore (Fig. 9) broad with pair of long curved outer projections, dorsally with long, dense patch of bristle-like hairs. Lateral view of pygophore as in Fig. 8, density of hairs increasing posteriorly. Paramere (Fig. 9) short, distinct, clove-shaped with blunt apex and without hairs. Dorsal view of the well developed endosomal sclerite as in Fig. 12. Male (macropterous) and female. Unknown. Differential diagnosis. The new species is closely related to Eotrechus kalidasa Kirkaldy, 1902, known from Burma and Assam, and possesses a very similar structure in regard to the fore femur, abdominal apex and pygophore. It can, however, be distinguished from other Indian congeners by the elongate, dark body; long antennae; slender and simple fore femur without any modifications; much longer sternum 7; broad pygophore, with a blunter apex when viewed laterally, and fringed with long hairs throughout, with the density of these hairs increasing apically; by the structure of proctiger, which is more elongate and distinctly bilobed; and the shape of the paramere, which is ‘clove’ shaped, without any hairs, and terminates in a blunt apex. Eotrechus fuscus is similar to E. kalidasa in possessing a rather large and well-developed male paramere, although this structure is of a different shape in the two species, being stouter basally and less expanded distally in E. fuscus. In addition, the shape of the lateral process on the pygophore, when viewed laterally (Fig. 8), is thicker and somewhat more curved in E. fuscus than in E. kalidasa. Finally, the proctiger of E. fuscus, when viewed dorsally (Fig. 11), has small, angulate lateral lobes that are missing in E. kalidasa. These genital characters, in combination with the darker ground coloration of E. fuscus, are sufficient to separate the two species. Etymology. The Latin adjective fuscus (- a, - um), meaning dark, refers to the dark black coloration of the species. Habitat. The type locality is a high altitude mountainous waterfall in Sikkim, in a pristine area. This species occurred on the vertical rock surfaces of the waterfall splashed with water and covered with moss and ferns. The habitat was disturbed to collect the specimen. Distribution. India, Sikkim, so far known only from the type locality., Published as part of Basu, Srimoyee, Chandra, Kailash, Venkatesan, Thiruvengadam & Icar-Nbair, 2017, Eotrechus fuscus sp. nov. from Northeastern India with a key to Indian species (Hemiptera: Heteroptera: Gerridae), pp. 391-398 in Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) (Acta. Ent. Mus. Natl. Pragae) 57 (2) on pages 392-397, DOI: 10.1515/aemnp-2017-0083, http://zenodo.org/record/5315963, {"references":["ANDERSEN N. M. 1982: Semiterrestrial water striders of the genera Eotrechus Kirkaldy and Chimarrhometra Bianchi (Insecta, Hemiptera, Gerridae). Steenstrupia 9 (1): 1 - 25."]}

Key to the known Indian species of Eotrechus (males) 1 Body mainly brown in color, covered with golden or green pubescence..................... 2 – Body mainly black in color, covered with golden pubescence..................................... 3 2 Fore femur greatly incrassate throughout or basally..................................................... 4 – Fore femur simple and very slender, ventral surface without spine-like hairs; pygophore of male with elongated postero-lateral projections and bearing brush-like hairs.......................................................................................................... E. kalidasa Kirkaldy, 1902 3 Body length less than 10 mm; fore femur moderately incrassate in basal part..............5 – Body length more than 10 mm; fore femur slender, without any modification, only slightly incrassate in basal part; pygophore broad with long hair tufts and a pair of long curved projections.............................................................................. E. fuscus sp. nov. 4 Body length more than 7 mm; genital segment large, ventrally flattened; pygophore sub-quadrangular, with a ventral, transverse depression and with lateral projections................................................................................................. E. brevipes Andersen, 1982 – Body length more than 7 mm; genital segment wide with almost straight postero-ventral margin; pygophore broad, suboval with paired long bristle-like black hair tufts lateroventrally................................................................. E. pilicaudatus Tran & Zettel, 2006 5 Male genital segment relatively large; pygophore suboval with a posteriorly-directed projection on each side, in lateral view, projection of pygophore with a small notch................................................................................................. E. longipes Andersen, 1982 – Male genital segment depressed and medially grooved; pygophore basally constricted with lateral projection on each side, in lateral view, projection of pygophore without a small notch........................................................................ E. terrestris Andersen, 1982, Published as part of Basu, Srimoyee, Chandra, Kailash, Venkatesan, Thiruvengadam & Icar-Nbair, 2017, Eotrechus fuscus sp. nov. from Northeastern India with a key to Indian species (Hemiptera: Heteroptera: Gerridae), pp. 391-398 in Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) (Acta. Ent. Mus. Natl. Pragae) 57 (2) on page 397, DOI: 10.1515/aemnp-2017-0083, http://zenodo.org/record/5315963, {"references":["ANDERSEN N. M. 1982: Semiterrestrial water striders of the genera Eotrechus Kirkaldy and Chimarrhometra Bianchi (Insecta, Hemiptera, Gerridae). Steenstrupia 9 (1): 1 - 25.","TRAN A. D. & ZETTEL H. 2006: Notes on Eotrechus Kirkaldy, 1902 (Heteroptera: Gerridae) with descriptions of two new species. Zootaxa 1353: 39 - 51."]}

Eotrechus longipes Andersen, 1982 (Figs 13–20) Material examined. INDIA: SIKKIM: 6 JJ 3 &female;&female; (apterous), West Sikkim, Rimbi waterfalls, 27.314035°N, 88.186561°E, alt. 4153 ft [= 1266 m a.s.l.], 11.v.2015, coll. S. Basu (NZC-ZSI); 2 JJ (apterous), 1 &female; (macropterous), 2 &female;&female; (apterous), West Sikkim, Phamrong falls, 27.357853°N, 88.234138°E, alt. 4872 ft [= 1485 m a.s.l.], 11.v.2015, coll. S. Basu (NZC-ZSI). Distribution. India: Arunachal Pradesh, Uttar Pradesh, West Bengal, Sikkim (THIRUMALAI 2002). New species for Sikkim., Published as part of Basu, Srimoyee, Chandra, Kailash, Venkatesan, Thiruvengadam & Icar-Nbair, 2017, Eotrechus fuscus sp. nov. from Northeastern India with a key to Indian species (Hemiptera: Heteroptera: Gerridae), pp. 391-398 in Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) (Acta. Ent. Mus. Natl. Pragae) 57 (2) on page 397, DOI: 10.1515/aemnp-2017-0083, http://zenodo.org/record/5315963, {"references":["ANDERSEN N. M. 1982: Semiterrestrial water striders of the genera Eotrechus Kirkaldy and Chimarrhometra Bianchi (Insecta, Hemiptera, Gerridae). Steenstrupia 9 (1): 1 - 25.","THIRUMALAI G. 2002: A checklist of Gerromorpha (Hemiptera) from India. Records of the Zoological Survey of India 100: 55 - 97."]}

Basu, Srimoyee, Chandra, Kailash, Venkatesan, Thiruvengadam, Icar-Nbair (2017): Eotrechus fuscus sp. nov. from Northeastern India with a key to Indian species (Hemiptera: Heteroptera: Gerridae). Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 57 (2): 391-398, DOI: 10.1515/aemnp-2017-0083, URL: http://dx.doi.org/10.1515/aemnp-2017-0083

Background Glycemic response, a trait that is tedious to be assayed in cereal staples, has been identified as a factor correlated with alarmingly increasing prevalence of Type II diabetes. Reverse genetics based discovery of allelic variants associated with this nutritional trait gains significance as they can provide scope for genetic improvement of this factor which is otherwise difficult to target through routine screening methods. Results Through EcoTILLING by sequencing in 512 rice accessions, we report the discovery of six deleterious variants in the genes with potential to increase Resistant Starch (RS) and reduce Hydrolysis Index (HI) of starch. By deconvolution of the variant harbouring EcoTILLING DNA pools, we discovered accessions with a minimum of one to a maximum of three deleterious allelic variants in the candidate genes. Conclusions Through biochemical assays, we confirmed the potential role of the discovered alleles alone or in combinations in increasing RS the key factor for reduction in glycemic response. Electronic supplementary material The online version of this article (doi:10.1186/s12870-016-0968-0) contains supplementary material, which is available to authorized users.