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Open Access
Hybridization using promising second generation inbred and molecular characterization of a the third generation inbreds of WCT coconut
(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2018) Hassain, N; KAU; Sujatha, R
The research project entitled “Hybridization using promising second generation inbred and molecular characterization of the third generation inbreds of WCT coconut (Cocos nucifera L.)” was carried out in the Department of Plant Breeding & Genetics, College of Agriculture, Padannakkad during the year 2016-2018. The major objectives of this study include development of D x T hybrids using promising palms in second generation (S2) inbreds of West Coast Tall (WCT) as male parent and Malayan Yellow Dwarf (MYD) as female parent and characterization of third generation (S3) inbred seedlings of superior S2 palms of WCT using RAPD analysis. For hybridisation, the male parent was selected from the superior inbred family based on the reports on morphological evaluation and estimation of inbreeding depression during the period 2013-2015 (Chethana, 2016). The family IIIS2-1 showed lowest inbreeding depression for yield related traits among 12 families followed by VS2-2. The palm 313 (IIIS2-1) and 225 (VS2-2) were selected as male parents. Superior MYD palm to be used as the female parent was selected from among the MYD palms available at CoA, Padannakkad based on the general features of mother palm selection (Nair et al., 2008). Observations were recorded from these parental palms which included 24 morphological characters. The male parents showed inbreeding depression for several vegetative characters such as stem girth, functional leaves etc and reproductive characters such as number of female flowers per inflorescence, setting percent and nut yield per palm per year, compared to WCT. The results showed that inbreeding depression for these characters was more in palm 313 (developed by selfing) than palm 225 (developed by sibmating). Total five nuts were harvested from MYD (two nuts by using pollen from palm 313 and three nuts using pollen from palm 225) during May 2018 and were sown in the nursery. Molecular characterization of the 15nos of S3 inbred seedlings of IIIS2 family planted in the field in replicated plots were done using RAPD. Genomic DNA was isolated from 15 seedlings of IIIS3 family among which 10 were produced by selfing the S2 palms (IIIS3-1) and 5 were produced by sibmating the S2 palms (IIIS3-2) along with COD, CGD and WCT. After DNA isolation, samples were subjected to RAPD analysis using 10 decamer primers namely OPAU02, OPBA3, OPAW14, OPAW19, OPAW12, OPAW13, OPAW13, OPAW09, OPAU03, OPAW08 and OPAW15 selected based on screening 30 primers. Using primer OPAW08, a band of size of ~400bp was specifically found in inbreds alone while it was absent in dwarfs and WCT seedlings. In OPAU 03 primer, band size of ~1200bp was absent in WCT but present in all inbreds and CGD. The sibmated inbred NL1 showed a distict pattern when amplified with OPAW 09 compared to all other inbreds. The primer produced a specific band of size ~1050bp only in the sibmated inbred CL1 and was absent in all other samples. Amplification with OPAW19 primer produced a banding pattern in which it mainly distinguished CGD from all other seedlings where there were only two bands while others were having six bands. Primer OPAU 02 produced two unique amplicons: 1100bp present in selfed inbred I1M1 TH2 and MYD; 1000bp present in COD and MYD. Genetic similarity among the 15 IIIS3 seedlings, CGD, COD, MYD and WCT was estimated by using of software DARwin (Darwin 6.Ink). The dendrogram indicated three major clusters in which the grouping of several inbreds along with WCT, COD and CGD may be an indication supporting the hypothesis that the dwarfs might have been originated from the talls during the course of evolution followed by selection. The two dwarfs present in the group are COD and CGD which are from Chavakkad area in Kerala and WCT is the most common cultivar of Kerala. As a future line of study, further evaluation of these S3 inbreds regarding the flowering time and yield characters has to be carried out to find out the genetic potential of these inbreds as breeding lines for producing superior hybrids. The seedlings to be emerged from the hybrid nuts produced in the present study, though limited in number, needs to be evaluated for important traits and the hybridisation programme using superior palms in S2 generation needs to be continued for production of more number of hybrid nuts.
Open Access
Effect of seed treatment on growth, seed yield and quality in Okra (Abelmoschus esculentus L. Moench
(Department of Seed Science and Technology College of Horticulture, Vellanikkara, 2018) Adersh, S; KAU; Dijee Bastian
The research work 'Effect of seed treatments on growth, seed yield and quality in okra (Abelmoschus esculentus L. Moench)', was conducted in the Department of Seed Science and Technology, College of Horticulture, Vellanikkara, during 2017-18 with an objective to find the effect of seed treatmentwith growth regulators on growth, seed yield and quality in okra and to delineate their effect on seed quality and longevity. Two separate experiments were conducted. Freshly harvested okra seeds of variety Arka Anamika, were treated with different concentrations of growth regulators namely GA3, IAA, NAA, Cycocel, Maleic hydrazide and Thiourea for two different time period (12 hours and 24 hours) and used to conduct the field experiment (Experiment 1) immediately. The experiment uses the treated seeds was laid out in Randomised Block Design with three replication and twenty five treatments including control. Observations on growth and yield parameters were recorded at appropriate stages. The results revealed that seed treatment with different plant growth regulators exhibited significant differences for all the characters studied. Growth characters like plant height, internode length, number of fruits per plant and seed yield per plant were found to be high in T24 (Thiourea 1000 ppm for 24 hours), while T16 (CCC at 150 ppm for 24 hours) and T14 (CCC at l50ppm for 12 hours) registered higher values for nodes per plant and branches per plant respectively. Among the treatments T3 (GA3 50 ppm for 24 hours) flowered early at 36.26 days. Higher values for fruit length and seeds per fruit were recorded in GA3 100 ppm for 24 hours (T4) and fruit weight was found to be higher in NAA 100 ppm for 24 hours (Tu). The seeds obtained under the field experiment were used to conduct the seed storage studies (Experiment II). The seeds from each treatment of experiment I were dried separately to a moisture content of less than 8 per cent and packed in 700G polythene covers and sealed. Seeds were stored under ambient conditions and seed quality parameters evaluated at monthly intervals for a period of seven months. Experiment II was laid out following a Completely Randomized Design (CRD) with twenty five treatments (To to TZ5) as in experiment I and three replications. Significant differences existed among the treatments for all seed quality parameters studied except time taken for 50% germination, seed moisture and seed microflora. It was clearly evident from the storage study that, as storage period increases the seed quality decreases irrespective of the treatments. In case of germination, all treatments including the control maintained the Minimum Seed Certification Standard (MSCS) of 65 percent up to fifth month of storage. At the end of the storage period (7 MAS) only two treatments (T11-NAA 50ppm for 24 hours and T3-GA3 50ppm for 24 hours) retained MSCS (65%). Vigour index I and II had higher values in Til which was statistically on par with TIZ, TlO, T3 and T4. Seed quality parameters such as germination, vigour indices and seedling dry weight decreased with the advancement of storage period, whereas EC of seed leachate, germination time, time taken for 50% germination increases over the storage period. The effect of growth regulators on seed microflora was found to be non-significant at the start and the end of the storage period. But the per cent of seed infection by seed microflora increased at the end of storage period, irrespective of the treatments. Ranking of characters in experiment I along with germination percent and vigour index I of experiment II was undertaken to identify the superior treatments. Based on the total score obtained GA3 at 50 ppm for 24 hours (T3) was adjudged as the best treatment followed by NAA at 50 ppm for 24 hours (T11). Hence it is concluded that soaking seeds with GA3 at 50 ppm and NAA at 50 ppm effectively enhances the growth, fruit and seed yield, seed quality and longevity in okra.
Open Access
Breeding for shattering resistance in rice (Oryza sativa L.)
(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2018) Anju, M Job; KAU; Biju, S
The research work 'Breeding for shattering resistance in rice (Oryza sativa L.)' was conducted in the Department of Plant Breeding and Genetics, College of Horticulture (COH), Vellanikkara, during the academic year 2017-2018. The research work was mainly divided into three experiments. Experiment 1 consisted of screening of rice genotypes for shattering resistance which was conducted at Agricultural Research Station (ARS), Mannuthy. After screening, four selected shattering resistant rice genotypes were crossed in Line x Tester pattern with three shattering prone high yielding varieties in experiment 2. In experiment 3 progenies were evaluated along with parents for shattering resistance. Shattering was measured based on Induced Random Impact method using a force gauge apparatus. Wide variability was found to exist among twenty five genotypes for yield and most yield attributes studied indicating ample scope for improvement through selection. High heritability coupled with high genetic advance as per cent of mean indicating the influence of additive gene action in the expression of trait were observed for days to fifty per cent flowering, flag leaf width, flag leaf length, panicle per plant, seed yield per plant and shattering per cent. Substantial improvement in the expression of these characters over base population can be expected through simple selection. Tillers per plant showed moderate heritability along with high genetic gain implying influence of both additive and non additive gene action in the expression of these characters. Improvement of these traits could be attained by following recurrent or reciprocal recurrent selection to exploit both additive and non-additive genetic components. Seed yield per plant recorded high significant correlation with number of tillers per plant, flag leaf width, number of panicles per plant and seeds per panicle and significant correlation with test weight. Shattering per cent recorded a high significant inter correlation with panicle length and significant inter correlation with kernel length. High estimates of general combining ability (OCA) over specific combining ability (SCA) is indicative of preponderance of additive gene action and it was evident in the case of days to maturity, flag leaf width, seeds per panicle and kernel width. Prevalence of non-additive gene action i.e., dominance and epistatic gene action in trait expression indicated by high SCA over OCA was registered for the remaining characters. When parents were evaluated on the basis of mean performance, it was evident that for seed yield per plant L2, L3 and T1 recorded a high response. The response recorded for panicle length and shattering per cent were exactly similar. When all the fourteen characters for the seven parents considered together, L2, L3 and T2 represented as best parents for yield and yield attributes and T1 recorded to be a moderate response. Evaluation of hybrids based on mean performance revealed that out of the twelve hybrids, H1, H2, H3, H4, H6 and H11 recorded a high response towards reduced shattering and H5 reported moderate response. Among the twelve hybrids H1 (L1 x T1), H2 (L1 x T2), H3 (L1 x T3), H5 (L2 x T1), H6 (L2 x T2) and H11 (L3 x T3) showed a high total response compared to the rest. Results from gca effects of parents indicated that L1 and T3 to be better combiner for reduced seed shattering indicating a scope for further utilization of these lines in plant breeding programmes for reduced shattering. When all the fourteen characters were considered, L2, T1, T2 and T3 recorded as better combiner. All the seven parents recorded to be moderate combiner for tillers per plant and flag leaf width. Scoring based on mean performance and combining ability effects for seed yield per plant revealed that, L2, L3 and T2 proved to be promising. T1, T2 and T3 proved to be promising parents for reduced seed shattering and T4 and Ll with a moderate response. When all the fourteen characters considered together L2, T1 and T2 were recorded as most promising parents.Specific combining ability studied among the cross combinations indicated that out of the twelve hybrids, H4, H5, H6 and H11 recorded high response and HI exhibited a moderate response for seed shattering. When the fourteen characters considered together, H3, H4, H5, H6, H8, H10 and H11 recorded to be better cross combination among the twelve characters. When mean performance and sea effect for all the fourteen characters for hybrids considered, the hybrids H1, H2, H3, H5, H6, and H11 reported high scores and H8 recorded moderate response. All the twelve hybrids recorded high significant heterobeltiosis for plant height, flag leaf width, panicles per plant, panicle length, test weight, kernel width, kernel length and shattering per cent. Based on the scoring for both mean performance and heterotic effect revealed that hybrids H5 recorded highest score followed by H3, H9, H11, and H1. Evaluation of hybrids based on mean performance, sea effects and heterosis revealed that hybrids H5, H6 and H3 recorded the first three positions among the twelve hybrids evaluated. Among this H5 and H6 have both the parents as better combiners. The remaining cross combination involving different combinations of parents viz., good x good, average x average, average x poor, poor x good, poor x average and poor x poor etc., can be used for transgressive breeding since there will be better recombinations in segregating generation.
Open Access
Developing dwarf specific scar markers from WCT inbreds of coconut (Cocos nucifera L.)
(Department of Plant Biotechnology, Vellanikkara, 2018) Anto, Varghese; KAU; Sujatha, R
Coconut is an important subsistence and cash crop in the humid tropical regions of the world. The coconut palm is often called “the tree of life” because of its numerous uses as food, drink, fuel, building materials and so on. Coconut cultivars are mainly classified into two: tall and dwarf. West Coast Tall (WCT) is the most common and superior tall cultivar extensively cultivated all over the west coast region, especially in Kerala. One of the main methods of crop improvement in coconut is hybridization between tall and dwarf types. However the heterozygous nature of tall types is a hurdle in selection of mother palms and seedlings. Efforts to develop homozygous inbreds of WCT were started as early as 1924. Chethana (2016) studied the extent of inbreeding depression in second generation (S2) inbred palms and recorded morphological observations of one year old third generation (S3) inbred seedlings. Based on height, she classified the S3 seedlings into Low, Medium and High, before planting in the field. She also carried out the characterization of selected third generation (S3) inbreds using RAPD marker system along with tall (WCT) and dwarf palms (COD, CGD). The results revealed two dwarf specific RAPD bands in two of the S3 seedlings belonging to IAS3-1 and IBS3-1 family, when amplified with primers OPAU03 and OPAW15. However, as RAPD markers have low specificity and sometimes lack repeatability, converting them into Sequence Characterized Amplified Region (SCAR) markers is more advantageous. A tall specific SCAR marker was reported in coconut using primer OPA 09 (Rajesh et al., 2013). The present investigation was carried out in the departments of Plant Biotechnology, College of Agriculture, Padannakkad and College of Horticulture, Vellanikkara during the period 2016-2018 was undertaken with an objective of developing SCAR markers from dwarf specific RAPD marker for screening superior inbreds with dwarfing nature. DNA samples were extracted from total 54 genotypes, 22 seedlings belonging to the inbred families IAS3-1and IBS3-1, 10 seedlings from other three families viz, IIS3, IIIS3 and VS3, 14 dwarf seedlings (including COD, CGD and MYD) and 8 tall seedlings (WCT). These were subjected to RAPD analysis using the 3 reported primers viz, OPAU 03, OPAW 15 and OPA 09. Though OPAU03 showed polymorphism between tall and dwarfs, the bands lacked repeatability and hence this was not included in further analysis. OPA 09, which was reported to produce a tall specific band (Rajesh et al., 2013), confirmed the result in the present study also. Primer OPAW15 was successful in amplifying a polymorphic band of size around 320 base pair specifically in dwarf seedlings and it was not present in the tall cultivar (WCT). The polymorphic dwarf specific band produced by primer OPAW 15 was eluted and cloned in pTZ57R/T vector and transformed into E. coli DH5 alpha cells. Cloned cells were subjected to blue white screening and transformed ones were selected, the plasmid was isolated and sequenced. The sequence after vector screening was subjected to homology search using BLASTn. The DNA sequence of polymorphic band showed similarity with chromosome 2 of Solanum lycopersicum. Based on the sequence, one pair of SCAR primer was designed and tested for dwarf specific band. Dwarf specific amplicon was found in all the dwarfs but absent in the tall WCT seedlings. Hence, this was used to screen the S3 inbred seedlings which were classified as Low, Medium, and High based on their height at the time of planting, to confirm the effectiveness of this classification based on morphology. The result showed that the dwarf specific marker is present in S3 inbreds belonging to Low and Medium types but absent in all those seedlings classified as ‘High’ based on height. This shows that the classification based on height in the one year old seedlings is effective to some extent. However, some of the seedlings in ‘Low’ and ‘Medium’ category lack the marker, which indicate that a classification based on morphological and molecular marker is more effective than classification based on morphology alone. The dwarf specific SCAR marker developed in the present study after validation using other tall and dwarf cultivars, along with the earlier reported tall specific SCAR marker can be successfully employed in breeding experiments for marker assisted selection. The SCAR markers which distinguish tall and dwarf coconut cultivars can be used in screening seedlings at an early stage which would be of immense importance to nurseries and growers while establishing coconut plantations.
Open Access
Phosphorous and boron interactions in black cotton soils of kerala with respect to groundnut (Arachis Hypogaea L.)
(Soil science and agricultural chemistry, Vellanikkara, 2018) Shaniba, M; KAU; Beena, V
Balanced supply of nutrients is one of the most important factors determining crop yield. Sometimes the applied nutrients may not be available for plant use, as their availability depends on interaction between nutrients. When the supply of one nutrient element affects the absorption and utilization of other nutrient element, the elements are said to be in interaction and interactions may be negative or positive. In Kerala, black cotton soils are seen in Chittur taluk of Palakkad district occupying an area of approximately 2000 ha. These soils are sandy clay loam, dark, calcareous, neutral to alkaline (pH 7.0 to 8.5), high in clay content and CEC. These soils are sufficient in all nutrients except phosphorus (P) and boron (B). Finding the interaction between Band P in black soils will help to understand the factors determining the availability of these nutrients to crops. The present study was carried out in College of Horticulture, Vellanikkara during 2016-18. The objectives of the study were to find out the interactions of boron and phosphorus in black cotton soils of Palakkad and to assess the treatment level of boron (B) and phosphorus (P) for maximizing the yield. The study consisted of a field experiment with groundnut variety, K-6 in black cotton soils of Chittur, Palakkad followed by analysis of soil, plant and pod samples taken from the experimental field. Soil samples were collected from different locations of Chittur and analyzed for available P and B. Field experiment was carried out where deficiency of both P and B was noticed. Experiment was laid out in factorial RBD with 17 treatments and 4 replications. Treatment combinations were made with four levels of P and four levels of B with soil test based recommendations as control. N and K levels are kept same (based on POP recommendations of KAU) for all treatments except for the first treatment where soil test based recommendations was given. P0 - 0 kg ha-1, P1 - 60 kg ha-1, P2 -75 kg ha-1 and P3 -90 kg ha-1 were the four levels of P and B0 - 0 kg ha-1, B1 - 5 kg ha-1, B2 - 10 kg ha-1 and B3- 15 kg ha-1 were the four levels of borax. super phosphate (SSP) was used as source of P and borax was used as source of B. Physical characteristics of soil viz., texture and bulk density were analyzed before experiment and chemical characteristics viz., pH, EC, organic carbon, N, P, K, Ca, Mg, S, Fe, Mn, Zn, Cu and B were analyzed before and after the experiment. parameters like plant height and number of leaves per plant were recorded at flowering, pegging, pod setting and harvest stages and yield parameters like number of pods per plant and yield were recorded at harvest stage. Plant nutrient content was analyzed and uptake was computed at different stages viz., flowering, pegging, pod setting and harvest stages whereas pod nutrient content and uptake was computed only at harvest stage. Soil nutrient status, plant nutrient content and uptake of nutrients were affected by main effect and interaction effect of P and B. Application of P at 90 kg ha-1 and B at 0 kg ha-1 resulted in highest plant height and number of leaves per plant. Application of P at 90 kg ha-1 and B at 5 kg ha-1 resulted in highest number of pods per plant and yield. Application of P at 90 kg ha-1 and B 0 kg ha-1 resulted in highest protein content in groundnut. Application of increased dose of P reduced availability of B due to anionic competition. Application of P reduced the availability of Fe, Mn and Zn in soil due to the formation of insoluble compounds like Fe-P, Mn-P and Zn-P. Application of P enhanced the availability of N. K content in soil was reduced with increased dose of P application. Ca and S were increased due to its supply through fertilizer in soil. Plant nutrient content showed a decreasing trend from flowering to harvest stage. Application of P enhanced plant and pod P content and application of B reduced plant and pod P content. Content of N, P, K, Ca and S was increased with increased levels of P and content of Fe, Mn, Zn and B was reduced with increased dose of P. Content of N, P, S, Zn and B were higher in pod than plant. Uptake of nutrient followed an increasing trend from flowering to harvest due to increased dry matter production. The uptake of N, P, S, Zn and B by pod was higher compared to plant uptake.
Open Access
Economics of dairying in Thrissur district
(Department of Rural Banking & Finance Managemnet , College of Cooperation, Banking & Management, Vellanikkara, 2017) Greeni T, Thankachan; KAU; Molly, Joseph
Open Access
Plant growth-promotion and root knot nematode management in tomato by Piriformospora indica and rhizobacteria
(College of Agriculture, Vellayani, 2016) Shilpa, Varkey; KAU; Anith, K N
The study entitled “Plant growth-promotion and root knot nematode management in tomato by Piriformospora indica and rhizobacteria” was conducted at the Department of Agricultural Microbiology College of Agriculture,Vellayani during the period 2014-2016 with the objective to assess the potential of the root endophytic fungus Piriformosporaindicaand plant growth-promoting rhizobacteria in improving plant growth and suppressing root knot nematode infestation in tomato. The experiment was conducted as in vitro and in vivo studies involving interaction assay between the biological agents and the nematode pest, andin vivo pot culture studies. Egg hatching and J2 mortality asinfluenced by treatment withrhizobacteriaand their cellfree extracts (CFE) were analyzed.Cell free extracts of rhizobacteria significantly reduced egg hatching and increased the mortality ofMeloidogyne incognitajuveniles. After 72 hours, the minimum egg hatching was with CFE of Pseudomonas fluorescensAMB8 (22.33 %) followed by B. amyloliquefaciens (22.66 %) and the maximum was with B. subtilis(27%).Juvenile mortality was highly influenced by the cell free extracts of all the isolates. Higher rate of mortality was observed with undiluted CFE than the diluted ones. Mortality percentage ranged from 68.21% to 99.71% with highest accounted for CFE of B. amyloliquefaciens. Treatment with undiluted CFE of P. indicaresulted in mortality of the J2 by 98% and egg hatching was reduced to 23.33%. Allthe rhizobacterial strains(1x107bacterial cell/ml)negatively influenced the egg hatching(from 30 to 50%) as compared to the control(99 % hatching). Upon 72 hours of incubation, there was only 30 % egg hatching in the case of egg masses treated with Pseudomonas fluorescensAMB8 and in the case of Bacillus amyloliquefaciensit was 30.66 per cent. However, reducing the cell concentration in the test suspension of all the rhizobacterial strains had positive effect on egg hatching. Treatments with cell suspension of all rhizobacterial strainsshowed significantly low mortality of J2 juveniles, with highest mortality forB. amyloliquefaciens (8.56 %) indicating less influence by the rhizobacteria as such. Piriformosporaindicashowed no egg parasitism.Compatibility between Piriformosporaindicaandrhizobacteriawas assessed by dual culture plate assayunder in vitrocondition and it was found that B. pumilus and Pseudomonas fluorescensAMB8 were compatible with the fungus though the test medium differed. The compatible bacteria as single inoculation and combination with P. indicawere used for in vivo analysis. Pot culture experiments using sterile planting medium with single inoculation of the selectedrhizobacteria, Piriformosporaindica, and theircombinationsin the presence or absence of nematode were carried out. All treatments with P. indicashowed root colonization by the fungus.In the presence of nematode, percentage root colonization was found to be increased and the highest was for combination of P. indica and P. fluorescens AMB8. Higher biometric characteristics were observed with nematode untreated plants for all parameters.In the nematode inoculated treatments, application of combination of P. indicaandP. fluorescensAMB8had positive effect on leaf number, fruit number, shoot weight and root weight when compared to the control.Treatment withP.indica resulted in formation of less galls/plant (33.30), egg mass/root system (3.41), eggs/egg mass (306.405), number of nematodes/g of root (54.415) and final nematode population/100cc soil (58) as compared to the control plants, where the values were 142.24, 24.91, 663.54, 220.57, 294.16 respectively. The study established the biocontrol potential of P.indicaagainst root knot nematode in tomato. Application of P. indica in the protray seedling production ensures better performance in terms of plant growth and suppression of root knot nematode infection in the main field.
Open Access
Development of root endophytic plant growth promoters as bio-inoculants for protray seedlings
(College of Agriculture, Vellayani, 2016) Vyshakhi, A S; KAU; Anith, K N
The study entitled “Development of root endophytic plant growth promoters as bio-inoculants for pro-tray seedlings” was conducted at College of Agriculture, Vellayani during the period 2013-15 with the objective to develop microbial root endophytic plant growth-promoters as bio-inoculants in pro-tray seedling production of major solanaceous vegetable crops chilli, tomato and brinjal. Microorganisms were isolated by triturating the roots of vigorously growing seedlings of tomato, brinjal and chilli after surface sanitization. Bacterial isolates were subjected to a preliminary screening on their respective hosts for plant growth promotion. Seedling vigour was assessed under green house condition in portrays using sterile planting medium. Endophytes with plant growth promoting ability selected through the preliminary screening were assessed under in vitro condition using dual culture plate assay for assessing the compatibility with Piriformospora indica (Pi). Piriformospora indica is a wide host root colonizing endophytic fungus which allows the plants to grow under extreme physical and nutrient stress condition. It belongs to the Sebacinales in Basidiomycota. Eight compatible bacterial endophytes (four from tomato, two from chilli and two from brinjal) were further evaluated for their growth promoting ability individually and in combination with P. indica. Bacterial inoculants were provided as seed treatment and the fungal inoculant as additive in the transplant medium. The bacteria were identified as Bacillus megaterium, Alcaligenes faecalis, Streptomyces leeuwenhoekii, Bacillus pumilus, Bacillus megaterium, Bacillus licheniformis, Bacillus thuringiensis thuringiensis based on 16s rRNA sequence homology. and BacillusThe plant growth promoting experiments in tomato indicated that the combination treatment of bacterial strain Streptomyces leeuwenhoekii with Pi was found to be statistically superior in shoot fresh weight, root fresh weight and root dry weight (1764.54 mg, 332.88 mg/plant and 26.45 mg/plant). Treatment Alcaligenes faecalis + Pi was found to be statistically superior in shoot length (15.23 cm) followed by the treatment Streptomyces leeuwenhoekii + Pi (14.45 cm). All the treatment were found to be superior over control. Root colonization by P. indica was not found to be influenced by the combined application with endophytic bacteria. By assessing the plant growth promotion in brinjal, significantly higher values with respect to shoot fresh weight, and root fresh weight ( 844.27 mg/plant, 83.03 mg/plant) were observed with the plant treated with endophytic bacterial isolate. Bacillus thuringiensis + P. indica showed superior mean height of 6.95 cm which was on par with Bacillus thuringiensis (6.74 cm). However the combination treatment of endophytic isolates with P. indica showed superior values compared to control. Analising the efficacy of the endophytic isolates in chilli for plant growth promotion indicated that treatment with the endophytic isolate Bacillus megaterium was found to be have significantly superior values in leaf number, shoot length, shoot fresh weight, and shoot dry weight (5.66, 11.93 cm, 855.20 mg/plant and 87.97 mg/plant). All the treatments including the combinations were found to be superior to control. P. indica has capability to induce resistance against biotic and abiotic stress, including drought, salinity resistance and bacterial, fungal and virus infection in plants. The current experiment suggest that native root endophytic bacteria can be used in combination with P. indica as far as plant growth is concerned. Further studies are required to assess the potential of such combinations in combating drought, salinity etc. plant diseases and helping the plant overcome
Open Access
Evaluation of cabbage ( Brassica oleracea L. var. capitata ) Genotypes for compactness and internal tipburn resistance under rain shelter
(College of Horticulture, Vellanikkara, 2016) Ningappa, Kirasur; KAU; Indira, P
The experiment entitled “Evaluation of cabbage (Brassica oleracea L. var. capitata) genotypes for head compactness and internal tipburn resistance under rain shelter” was carried out in the department of Olericulture, College of Horticulture, Vellanikkara during the period from May to September 2015. The major objectives of the study were to identify compact genotypes with high yield for rain shelter cultivation, to identify genotypes with internal tip burn resistance, a calcium related physiological disorder and also to study the effect of calcium foliar application on the incidence of internal tip burn. Seven cabbage genotypes were evaluated with three different calcium foliar treatments (0%, 0.5% and 1.5%). All the cabbage genotypes showed significant difference with respect to qualitative and quantitative characters studied. Number of wrapping leaves, head length, head breadth, net head weight, head index, harvest index and head compactness directly contributed towards yield. The minimum number of wrapping leaves (8.60) was in genotype G 1 (NS 43) and the genotype G 8 (Saint) recorded the minimum number of non-wrapping leaves (7.70) . The genotype G 1 (NS 43) recorded maximum plant spread (50.70 cm), head length (12.91cm), head breadth (13.40 cm), net head weight (787.33 g) and gross head weight (1136.66 g). The genotype G 4 (F 1 Border 777) recorded the maximum head index (1.31), but harvest index was maximum for the genotype G 8 (69.60 %). All the genotypes formed very compact heads in all Ca foliar treatments, except G 1 (NS 43) which formed loose heads in C 2 (Ca 1.5 %) treatment, medium compact heads in control (C 0 ) and C 1 (0.5 %) treatments. All the genotypes produced conical heads except G 1 (NS 43) which produced round heads. The genotype G 5 (Green Voyager) recorded maximum yield of 6.40 kg per plot. Among the seven genotypes, only the genotype G 1 (NS 43) recorded slight tipburn incidence (4.16 %). Genotypes G 3 (Super Ball 50), G 4 (F 1 Border 777), G 6 (Mahy 118) and G 8 (Saint) were free from pest incidence and genotypes G 2 (Green Challenger), G 5 (Green Voyager) and G 6 (Mahy 118) were free from disease incidence.Effect of different levels of calcium foliar application and the interaction effect were non-significant in most of the characters. However the interaction G 4 C 0 recorded the lowest stalk length (5.25 cm) and interaction G 1 C 2 recorded the highest gross head weight (1365 g). The interaction G 1 C 2 recorded slight incidence of tipburn (1.78 %). There was no pest incidence in the interactions G 8 C 0, G 6 C 1, G 4 C 0 and G 3 C 1. The interactions G 5 C 0, G 2 C 0 and G 6 C 2 registered no disease incidence. Soil samples were collected from all the experimental plots before and after raising the crop. Soil samples were analysed for pH, organic carbon, available P, K, Ca, Mg, Fe and Mn content. There was no significant difference with respect to soil pH, organic carbon, available P, K, Ca, Mg, Fe and Mn content among the plots before and after raising the crop. Index leaf (recently matured wrapping leaf and head) samples were collected from internal tipburn susceptible genotype G 1 (NS 43) and high yielding, resistant genotype G 5 (Green Voyager). Plant samples were analysed for N, P, K, Ca, Mg, Fe and Mn content both in leaf and head. Here also there was no significant difference among genotypes for N, P, K, Ca, Mg, Fe and Mn content both in leaf and head samples. The foliar application of Ca increased leaf calcium concentration in both the genotypes. Maximum leaf Ca content was recorded in the interaction G 5 C 2 (1.20 %) and it was lowest in G 1 C 2 (1.17 %). The genotype G 5 (Green Voyager) produced very compact heads, higher net head weight (1005.83 g), yield per plot (6.40 kg) and high benefit-cost ratio (1.52). It was also resistance to internal tipburn. Hence this genotype can be recommended for off-season cultivation under rain shelter in the central plains of Kerala. From the present study it was found that internal tipburn incidence in cabbage is genotype specific and it can be reduced by Ca foliar application. Only the genotype G 1 (NS 43) was susceptible to internal tipburn among the seven genotypes. Hence more number of genotypes are to be screened in further experiments.

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