Kerala Agricultural University, Thrissur

The history of agricultural education in Kerala can be traced back to the year 1896 when a scheme was evolved in the erstwhile Travancore State to train a few young men in scientific agriculture at the Demonstration Farm, Karamana, Thiruvananthapuram, presently, the Cropping Systems Research Centre under Kerala Agricultural University. Agriculture was introduced as an optional subject in the middle school classes in the State in 1922 when an Agricultural Middle School was started at Aluva, Ernakulam District. The popularity and usefulness of this school led to the starting of similar institutions at Kottarakkara and Konni in 1928 and 1931 respectively. Agriculture was later introduced as an optional subject for Intermediate Course in 1953. In 1955, the erstwhile Government of Travancore-Cochin started the Agricultural College and Research Institute at Vellayani, Thiruvananthapuram and the College of Veterinary and Animal Sciences at Mannuthy, Thrissur for imparting higher education in agricultural and veterinary sciences, respectively. These institutions were brought under the direct administrative control of the Department of Agriculture and the Department of Animal Husbandry, respectively. With the formation of Kerala State in 1956, these two colleges were affiliated to the University of Kerala. The post-graduate programmes leading to M.Sc. (Ag), M.V.Sc. and Ph.D. degrees were started in 1961, 1962 and 1965 respectively. On the recommendation of the Second National Education Commission (1964-66) headed by Dr. D.S. Kothari, the then Chairman of the University Grants Commission, one Agricultural University in each State was established. The State Agricultural Universities (SAUs) were established in India as an integral part of the National Agricultural Research System to give the much needed impetus to Agriculture Education and Research in the Country. As a result the Kerala Agricultural University (KAU) was established on 24th February 1971 by virtue of the Act 33 of 1971 and started functioning on 1st February 1972. The Kerala Agricultural University is the 15th in the series of the SAUs. In accordance with the provisions of KAU Act of 1971, the Agricultural College and Research Institute at Vellayani, and the College of Veterinary and Animal Sciences, Mannuthy, were brought under the Kerala Agricultural University. In addition, twenty one agricultural and animal husbandry research stations were also transferred to the KAU for taking up research and extension programmes on various crops, animals, birds, etc. During 2011, Kerala Agricultural University was trifurcated into Kerala Veterinary and Animal Sciences University (KVASU), Kerala University of Fisheries and Ocean Studies (KUFOS) and Kerala Agricultural University (KAU). Now the University has seven colleges (four Agriculture, one Agricultural Engineering, one Forestry, one Co-operation Banking & Management), six RARSs, seven KVKs, 15 Research Stations and 16 Research and Extension Units under the faculties of Agriculture, Agricultural Engineering and Forestry. In addition, one Academy on Climate Change Adaptation and one Institute of Agricultural Technology offering M.Sc. (Integrated) Climate Change Adaptation and Diploma in Agricultural Sciences respectively are also functioning in Kerala Agricultural University.

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Open Access
Cryopreservation of chethikoduveli (Plumbago rosea L.) and assessment of genetic fidelity of regenerated plantlets using molecular markers
(Department of Plant Biotechnology, College of Agriculture, Vellayani, 2014) Anand, Vishnu Prakash; KAU
Investigations on “Cryopreservation of Chethikoduveli (Plumbago rosea L.) and assessment of genetic fidelity of regenerated plantlets using molecular markers” were carried out at the Department of Plant Biotechnology, College of Agriculture, Vellayani during 2011-2013. Plumbago rosea var. Agni plants were collected from AMPRS, Odakkali, Ernakulam and maintained at the Department of Plant Biotechnology, College of Agriculture, Vellayani as source of explant during the course of the study. The objectives of the present study was to standardise cryopreservation protocol by encapsulation dehydration technique for long term conservation of P. rosea and genetic fidelity assessment of plantlets recovered and regenerated from cryostorage using molecular markers. The project was carried out in two phases viz., in vitro regeneration and in vitro conservation by cryopreservation of P. rosea. In vitro regeneration protocol was optimised for P. rosea var. Agni. Various steps of in vitro regeneration viz., surface sterilization, axillary shoot proliferation, in vitro rooting and acclimatization and planting out has been standardised. For surface sterilizing, single nodal explants (3-4 cm long) were subjected to fungicide treatment with 0.1 per cent carbendazim 50 per cent W. P. (for 30 min) followed by aseptic sterilisation dip with absolute alcohol. Further, the explants were surface sterilised with 0.2 per cent mercuric chloride (for 5 min) which gave 100 per cent survival without any contamination. Enhanced release of axillary buds from single nodal explants, with maximum shoot proliferation (5.28 shoots/culture) was obtained in the medium, MS + BA 1.5 mg l-1 + IAA 1.0 mg l-1. The best response (10.67 roots/culture) of in vitro rooting of plantlets was obtained in the medium, MS + NAA 1.0 mg l-1. In vitro rooted plants gave a maximum survival rate of 76 per cent and 72 per cent, when planted out in potting media consisting of red soil and coir pith (3:1) and red soil and coir pith (2:1) supplemented with VAM respectively at 25 per cent shade. In cryopreservation studies, preconditioning treatment (sucrose 0.5 M for 7 days) recorded maximum shoot proliferation (2.67 shoots/culture) when nodal segments with single axillary bud were cultured on MS + BA 1.5 mg l-1 + IAA 1.0 mg l-1 medium. Among different encapsulation treatments, maximum shoot proliferation of (2.31 shoots/culture) was obtained in beads formed with sodium alginate 2.5 per cent and calcium chloride 100 mM, when cultured on the medium, MS + BA 1.5 mg l-1 + IAA 1.0 mg l-1. Pre-culture medium supplemented with sucrose 0.5 M for 3days gave maximum shoot proliferation (3.44 shoots/culture) when cultured on the medium, MS + BA 1.5 mg l-1 + IAA 1.0 mg l-1. A desiccation duration of 5 h at 18.13 per cent moisture level was found to be most effective giving 66.67 per cent survival and 62.50 per cent regeneration on thawing and culturing on the recovery medium MS + BA 1.5 mg l-1 + IAA 1.0 mg l-1. The beads when stored in liquid nitrogen for different duration and cultured on recovery medium did not show any significant variation with respect to survival per cent. RAPD markers were tried to study the genetic fidelity of the regenerated plantlets from encapsulated and cryopreserved axillary buds. Six primers were screened and RAPD banding patterns of the cryoregenerated plantlets and control plants were compared. Polymorphism was not found with any of the primers tested. RAPD profiles of cryoregenerated plantlets were identical to those of the control. The in vitro regeneration protocol optimized included surface sterilization of single node cuttings with 0.2 per cent HgCl2 for 5 min, axillary shoot proliferation in MS medium supplemented with BA 1.5 mg l-1 and IAA 1.0 mg l-1, in vitro rooting in MS medium supplemented with NAA 1.0 mg l-1 and planting out in potting medium, red soil and coir pith (3:1). The protocol for encapsulation dehydration technique of cryopreservation was standardised for the axillary buds of P. rosea with preconditioning in semi solid MS medium supplemented with sucrose 0.5 M for 7 days, encapsulation using sodium alginate 2.5 per cent and calcium chloride 100 mM followed by pre-culture in liquid MS supplemented with sucrose 0.5 M for 3 days and 5 h dehydration (MC 18.13 %), rapid freezing in LN for at least 2 h and recovery in the medium MS + BA 1.5 mg l-1 + IAA 1.0 mg l-1. The cryopreservation protocol using encapsulation-dehydration technique standardised could be utilised for long-term conservation of P. rosea.
Open Access
Development of an in vitro regeneration system and validation of genetic stability in phalaenopsis hybrid winter spot with molecular marker
(Centre for Plant Biotechnology and Molecular Biology, College of Horticulture, Vellanikkara, 2016) Asha Amal, Raj; KAU; Lissamma, Joseph
Phalaenopsis “Moth Orchids” are among the most beautiful flowers in the world. This genus has economic value for pot plant and cut flower production and is distributed throughout Southeast Asia. Most popular method of propagation for orchid is through in vitro propagation, as it produces large number of clones in relatively short duration. Despite its potential to produce numerous plants from a single leaf segment, it is liable to unpredictable mutations or somaclonal variation during the process of multiplication. Variation can arise due to many reasons such as type of media, plant growth regulators and its concentration, type of explants and number of subculture cycles. The percentage of the variation can range from 0-100% depending on varieties with an average of 10% among Phalaenopsis (Tokuhara and Mii, 1993). So the present investigation on “Development of an in vitro regeneration system and validation of genetic stability in Phalaenopsis hybrid Winter Spot with molecular marker” was taken up at the Center for Plant Biotechology and Molecular Biology, College of Horticulture from 2013-2016. Flowering mother plants of Phalaenopsis hybrid Winter Spot were used as explant source. Among the explants namely inflorescence node, transverse thin cell layer of leaf and root segments used for tissue culture study in this orchid, inflorescence node was the best with respect to culture response. The best surface sterilization treatment for leaf explants identified was treatment 0.1% bavistin + prill 2 drops (30 min) and 0.1 per cent HgCl 2 ( 8 min) which give maximum per cent of culture survival and minimum contamination rate. The best surface sterilization treatment for inflorescence node identified was treatment with 0.1% bavistin + 2 drops prill (30 min) , one minute dip in 70 per cent ethanol and 0.1% HgCl 2 (7 min).From different basal media (full MS and 1⁄2 MS) tried, response was observed only in the medium of Full MS for inflorescence node. Among the different growth regulators tried, MS medium supplemented with BA and TDZ was found to give good shoot regeneration from inflorescence node explants. MS +2mgl -1 TDZ recorded highest percentage (80%) of culture establishment, followed by MS + 4.5 mgl -1 of BA (55%) per cent of sprouting. Among the explants tried, only inflorescence node responded with sprouting. Root segment remained as such without any change, whereas leaf explants remained green up to 2 weeks, thereafter started drying in all the growth regulators combination. For induction of multiple shoot, MS medium supplemented with 4.5 mgl -1 BA resulted in the highest average number of multiple shoot (4.15). Elongation and rooting was observed in MS medium supplemented with BA 4.5mgl-1 +IAA 1mgl -1 with 80 % rooting. Root initials were observed 50 days after inoculation. The potting media, charcoal, brick pieces and sphagnum moss in the ratio of 1:1:1 was found ideal for hardening of Phalaenopsis hybrid winter spot with 100% survival. Genetic stability studies using RAPD marker were carried out with the mother plants along with three regenerants each. Six primers were selected based on DNA amplification pattern. In RAPD assay, M1 mother plant recorded the highest average polymorphism of 19.7% and M3 mother plant recorded the least average polymorphism of 8.18%. Using NTSYS software, the similarity coefficients for first, second and third plant between M1 mother plant, M2 mother plant and M3 mother plant and corresponding regenerants were 0.91, 0.92 and 0.93 respectively. In fourth plant, the similarity coefficient exhibited 100% similarity between mother plant, the first clone C1 and third clone C3. The established micropropagation protocol can be used with suitable modification for large scale production of other Phalaenopsis varieties.
Open Access
Characterisation of Pathogenesis related proteins for anthracnose resistance in vegetable cowpea, Vigna spp.
(Centre for Plant Biotechnology and Molecular Biology, College of Horticulture, Vellanikkara, 2013) Agatha Shiny, A; KAU; Deepu Mathew
Cowpea (Family: Fabaceae) is an important pulse cum vegetable crop of suitable for the tropical and sub-tropical regions of the world. The grain type cowpeas better tolerates the biotic and abiotic stresses against the vegetable types. Under humid conditions, vegetable types, especially the pole types are susceptible to many diseases and among them, anthracnose caused by Colletotrichum lindemuthianum (Sacc. & Magn.) Br. and Cav. is very severe. In Kerala, complete yield loss in vegetable cowpea is reported due to anthracnose during monsoons. The study entitled “Characterization of pathogenesis related proteins for anthracnose resistance in vegetable cowpea, Vigna spp.” was carried out with objective to develop the protein profiles of resistant and susceptible bush and pole genotypes through SDS-PAGE analysis at different time intervals of infection and to characterize the differentially expressed proteins by MALDI-TOF followed by in-silico analyses. Two bush type varieties Pusa Komal and Kanakamony, the former reported to be highly susceptible and the latter immune to anthracnose and two pole type varieties Lola and Arimbra Local, of which the former susceptible and the latter resistant were used in the study. Pure culture of the pathogenic fungus was developed and maintained on selective medium (Neopeptone-Glucose-Agar) at the Dept. of Plant Pathology. The identity of Colletotrichum lindemuthianum has been established from the spore characteristics observed under phase contrast microscope and the pathogenicity was confirmed through artificial inoculation under controlled conditions. The pot culture experiment was conducted with 50 pots per variety. Artificial inoculation of pathogenic fungus was done and the leaf samples were collected at 0, 6, 12, 18, 24, 48, 72, 96, 120, 144,168 and 192 hours after artificial inoculation. The total protein was extracted using Tris-HCl buffer (pH-7.5), quantified using spectrophotometer and analyzed by SDS-PAGE method. The defense enzymes like peroxidase (PO), polyphenol oxidase (PPO) and phenylalanine ammonia-lyase (PAL) were assayed. By artificial inoculation, disease responses for anthracnose were confirmed to be highly susceptible in Pusa Komal and Lola; highly resistant in Arimbra Local and immune in Kanakamony. Protein expression was found to be higher from the initial hours in resistant varieties whereas in susceptible varieties, the expression was reduced immediately after infection then peaked at 18hr and gradually decreased later on. Two prominent and differentially expressed protein bands at 56 kD and 14 kD were sequenced in MALDI-TOF to obtain the peptide mass fingerprint. Through in-silico analyses using Mascot server software, they were identified to be the large and small subunits of the chloroplastic enzyme RuBisCo. Thus the capability of a variety to maintain high levels of RuBisCo was found to be the deciding factor for anthracnose disease resistance. Further, protein profiles developed after purification of proteins by dialysis have clearly identified the differentially expressed band at 29 kD in the resistant varieties which is in the size range of already reported PR proteins. PO and PAL activities were proportionate to the resistance behavior, with the peak values at 18 and 24 hr after inoculation. With the results of this study, these defense enzymes are recommended as biochemical markers for identifying the resistance in the accessions. Capability to maintain higher levels of RuBisCo, PO and PAL enzymes is the characteristic of anthracnose resistant vegetable cowpeas and the future breeding programmes could be oriented in this direction
Open Access
DNA fingerprinting of selected black pepper (piper nigrum L.) varieties.
(Centre for Plant Biotechnology and Molecular Biology, College of Horticulture, Vellanikkara, 2011) Manjunath, Mogalayi; KAU; Nazeem, P A
Black pepper (Piper nigrum L.) famous as “Black Gold” and also known as “King of Spices” is one of the important agricultural commodities of commerce and trade in India since pre-historic period. The crop is the major source of income and employment for rural households in the predominantly pepper growing State of Kerala where more than 2.5 lakh farm families are involved in pepper cultivation. Karnataka, Tamil Nadu are the other major pepper producing States in the country. Kerala accounts for 80-90% of the total pepper production in the country. Idukki and Wynadu are the two major pepper producing districts in Kerala. Different cultivars/varieties are popular among the farmers and there phenotypic identity is not very distinct. The study entitled “DNA fingerprinting of selected black pepper (Piper nigrum L.) varieties” was carried out at the Centre for Plant Biotechnology and Molecular Biology, College of Horticulture during the period 2009-2011. The objectives of the study were to characterize the released black pepper varieties of KAU using different molecular markers - RAPD, ISSR and SSR and to develop DNA fingerprint with which the variety could be identified and its fidelity detected. Seven black pepper varieties (Panniyur 1 to Panniyur 7) collected from Pepper Research Station, Panniyur and maintained at CPBMB, COH were used for the study. DNA extraction was done with CTAB (Rogers and Benedich, 1994) method with slight modification. The RNA contamination was completely removed through RNase treatment. Good quality DNA with UV absorbance ratio (A260/A280) 1.80 - 1.89 was used for further analysis. The PCR conditions were optimized for RAPD, ISSR and SSR assay. 30 RAPD, 34 ISSR and 29 SSR primers were screened with bulked DNA of black pepper varieties for amplification and those which gave reliable distinct banding pattern were selected for further amplification and fingerprinting. The PCR products obtained from RAPD, ISSR and SSR analysis were separated on 1.3 to 2 percent agarose gel and the amplification patterns recorded. The genomic DNA from each variety was amplified with 10 each of selected RAPD and ISSR primers and 8 SSR primer pairs. The amplification pattern was scored and depicted to develop fingerprint for each variety. The Resolving power (Rp) worked out for the different primers ranged between 7.42 to 9.42 in RAPD and 5.42 to 12.28 in ISSR analysis; indicating the capacity of the primers selected to distinguish the varieties. The Polymorphic Information Content (PIC) varied from 0.86 to 0.90 for RAPD analysis and it was between 0.80 and 0.89 in ISSR analysis indicating the variability among the genotypes. Distinct bands were used to develop DNA fingerprint of black pepper varieties Panniyur 1 to Panniyur 7 through RAPD, ISSR and SSR analysis. Sharing of amplicons developed for each primer with other varieties was also analyzed and demarcated with different colour codes in the fingerprints developed. Most of the amplicons were found shared among the varieties. However, the pattern of sharing was different and good enough to separate out the varieties. Combined DNA fingerprint of each variety with RAPD, ISSR and SSR data was also developed. The amplification pattern observed in RAPD, ISSR and SSR analysis was scored and analyzed for quantifying the variability among the varieties. The computer package NTSYS-Pc was used for cluster analysis. Maximum variability observed was 48 percent for the variety Panniyur 4. The varieties Panniyur 1 and Panniyur 3 having the same parentage indicated 76 percent similarity. The fingerprint developed was good enough to provide varietal identity and the analysis could reveal variability/relatedness among the seven varieties. Separate and combined fingerprints were developed for all the seven varieties through RAPD, ISSR and SSR analysis. The DNA fingerprints thus developed could be utilized for the variety registration and settling IPR issues.
Open Access
Molecular characterization of katte mosaic virus of cardamom ( Elettaria cardmomum Manton )
(Centre for Plant Biotechnology and Molecular Biology, College of Horticulture,Vellanikkara, 2016) Abida, P S; KAU; Manglam Arya
Cardamom ( Elettaria cardamomum Maton) considered as “Queen of Spices” belongs to the family Zingiberaceae. Due to its aroma, cardamom is one among the most expensive spices in the world. Cardamom is infected by several fungal, bacterial and viral diseases. Katte or Cardamom mosaic disease is the most destructive viral disease affecting cardamom plantations worldwide. The disease is caused by Katte mosaic virus or Cardamom mosaic virus (CdMV) and spreads through infected suckers or through aphid Pentalonia nigronervosa Coq. The loss in yield due to katte disease ranges from 38 to 69 per cent and when infection occurs at early stage, the loss is complete. Management of katte disease totally depends on the use of disease free planting materials. As the infected plant often remains symptomless, identification and diagnosis of the virus becomes difficult at early stages. The present study was undertaken to develop serological and PCR based methods for identification and characterization of CdMV of cardamom. The infected and healthy samples were collected from four locations of Idukki and two locations of Wayanad districts of Kerala. The viral protein was isolated and purified from infected samples and SDS-PAGE analysis of purified protein from infected plants revealed the presence of 37 kDa band of viral coat protein. The purified protein from the infected plants was further used as antigen for the production of polyclonal antibody against CdMV in 6-9 month old rabbit. The rabbit was immunized with 5 mg of purified protein. The blood sample from the immunized rabbit was collected and the antibody was purified. The ODD (Ouchterlony Double Diffusion) assay was performed to standardize the titre of the antibody and results had shown that antigen-antibody complex was formed in 1:10, 1:100 and 1:150 dilutions of primary antibody. The indirect ELISA was carried out with 1:10, 1:100 and 1:150 dilutions of primary antibody and 1:200 dilution of secondary antibody. It was found that virus was easily detected in the crude extract of infected leaves with 1:100 dilution of primary antibody. Indirect ELISA was also performed for investigating the serological relationship of Katte mosaic virus with other viruses. The result of indirect ELISA revealed that the crude sap of infected cardamom leaves cross reacted with the antibody specific for Banana Bract Mosaic Virus (BBrMV) which also belongs to same potyvirus group. For the detection of CdMV through RT-PCR, the total RNA was isolated from the infected and healthy plants using Trizol and converted to cDNA. A total of 11 primers were designed for the amplification of coat protein gene of the virus using Primer 3 software. The primers designed were used for synthesis of second strand of cDNA and presence of virus was detected. Out of 11 primers, 8 primers were able to amplify the coat protein gene of the virus in infected plants. The band size of 250, 650, 750 and 950 base pairs were observed in infected plant but not in healthy plant samples. The viral amplicons of 250, 950, 750, 650 base pairs were generated with primers CP-2, CP-9, CP-10 and CP-11 respectively. These amplicons were further eluted, reamplified and sequenced. The nucleotide sequence annotated using bioinformatics tools BLASTn and BLASTx. The result of BLASTn showed 90 to 100 per cent nucleotide sequence similarity with CdMV whereas; the result of BLASTx revealed that the sequence had 55-100 per cent similarity with the coat protein of CdMV. The phylogenetic analysis was performed using 950 bp products generated with CP-9 primer. The phylogenetic tree was developed using MEGA.7 software by utilizing neibhourhood joining method. The result of phylogenetic analysis revealed that the isolates of Ambalavayal, Meppadi and Myladumpara are closely related and also related to isolates of Irettyar and Paravalam whereas, Pampadumpara isolate showed more variation to the above isolates. The methods developed in the present study are useful in detecting the Katte mosaic virus or Cardamom mosaic virus in the infected leaf samples of cardamom. The method will be useful in virus indexing, quarantine management in germplasm exchange, germplasm management, supply of disease free planting materials to the farmers and also for selecting the resistant line or cultivar for large scale production or incorporation in breeding programme for crop improvement.
Open Access
Molecular characterization of candidate gene for pungency in Capsicum spp.
(Centre for Plant Biotechnology and Molecular Biology, College of Horticulture,Vellanikkara, 2016) Anju Viswanath, KAU; Deepu Mathew
Chilli, also known as “Wonder spice”, has been cultivated since 3000 BC. Out of the 21 identified species of chilli, C. annuum, C. chinense, C. frutescens, C. baccatum and C. pubescens are the domesticated species. It is a major vegetable cum spice crop which can impart pungency, colour and aroma to the human foods. Pungency is one of the most important and peculiar character of all the species belonging to the genus Capsicum. Capsaicinoids are the alkaloid compounds which are responsible for pungency in chilli. Because of the nutraceutical properties possessed by these capsaicinoids, it has much importance in manufacturing several drugs. Though so many studies are conducted to understand the genetic mechanisms behind pungency, the gene action responsible for its production is still an enigma. This experiment was undertaken with the objective to assess the molecular mechanisms behind different levels of pungency in different species of Capsicum. The investigations were carried out in ten chilli genotypes namely, Ujwala, Anugraha, Byadagi Dabbi, Byadagi Kaddi, paprika Kt-Pl-19 and bell peppers Arka Gaurav and Arka Mohini (C. annuum), Vellayani Thejus (C. chinense) and White Khandari, Vellayani Samrudhi (C. frutescence). Among the genotypes Anugraha, Ujwala, Vellayani Thejus, Vellayani Samrudhi and White Kandari are pungent lines and Kt-Pl-19, Byadagi Dabbi, Byadagi Kaddi, Arka Mohini and Arka Gaurav are non-pungent lines. Good quality genomic DNA has been extracted from all the genotypes with an absorbance ratio ranging from 1.79 - 1.85 and concentration more than 1000 ng/μl. The DNA was screened with five pungency specific SCAR (Sequence Characterized Amplified Region) primers. Among the five SCAR primers used, three were specific for Pun1 locus (MAP1F/R, Pun1 1 fwd1/rev, Pun1 3 fwd/rev1) and two were specific for CS (Capsaicinoid synthetase) gene (CSF1/R2, BF7/R9). Pun1 and CS are the loci responsible for the synthesis of putative acyl- transferase and capsaicin synthase enzymes leading to the synthesis of capsaicinoids. The results revealed that MAP1F/R is the most significant primer which gave distinct amplifications in both pungent lines and non-pungent lines. A 15 bp deletion was clearly identified in the non-pungent lines compared to the pungent lines. This resultii revealed that the 15 bp deletion in the non-pungent lines is the reason for the absence of pungeny in them. The other two primers Pun1 1 fwd1/rev, Pun1 3 fwd/rev1 gave amplification only for pungent lines in C. annuum and C. frutescence respectively since Pun1 1 and Pun1 3 are the mutant alleles of Pun1 locus present in the respective species. The capsaicin, which is a capsaicinoid compound contributing about 69 per cent of pungency, is produced with the help of the capsaicin synthase enzyme produced from the CS gene. The primers specific for the CS gene have amplified only in the pungent lines. This result revealed that the nucleotide change in the primer binding region is the reason for the absence of pungency in them. The amplicon sequences of CS gene was subjected to insilico analysis such as BLASTn and Clustal Omega, which identified that the CS gene whose location was not yet confirmed also resides within the Pun1 locus. The insilico analysis has also proven that the 15 bp deletion identified in the non-pungent lines were located at the ORF3 in the Pun1 locus. This deletion in the coding region significantly affects the capsaicinoid formation for the pungency. Irrespective of the species, the deletions occurring in the coding regions of the Pun1 locus and CS gene, are the reasons for the variation of pungency levels in chillies. All the five primers attempted were promising and can be utilized to distinguish the pungent and non-pungent lines even in the seedling stage and hence in marker assisted selection (MAS). Identification of the location of CS gene inside the Pun1 locus is the most striking finding of this study. From this it can be infered that Pun1 locus, which is in the chromosome 2 of chilli is the major deciding locus for the production of capsaicinoids.
Open Access
Genetic transformation of Amorphophallus paeoniifolius (Dennst) Nicolson
(Department of Plant Biotechnology, College of Agriculture, Vellayani, 2014) Leen Abraham, N; KAU; Makeshkumar, T
A study on Agrobacterium-mediated genetic transformation of Amorphophallus paeoniifolius (Dennst.) Nicolson was conducted at the Central Tuber Crop Research Institute, Sreekariyam, Thiruvananthapuram during 2013- 2014. Calli were initiated using petiole and leaves of in vitro plantlets of elephant foot yam cv. Gajendra in callus induction media. After four weeks of incubation, actively dividing globular, hard and creamy white calli were developed. Subculture of developed calli was repeated periodically (20 days) in CIM with an approximate size of one cm2. 15 days old calli was found to be suitable for transformation study. Calli sufficient for the transformation study was obtained after 3 months of subculture. Experiments were conducted to evaluate the sensitivity of elephant foot yam calli to different doses of antibiotics viz. geneticin, hygromycin, ticarcillin. It was observed that complete death and discoloration of the calli obtained with 20 mgl-1 geneticin and 10 mgl-1 hygromycin from sixth week treatment. Statistical analysis of sensitivity response of calli indicated that LD100 was 20 mgl-1 and 5 mgl-1 with geneticin and hygromycin respectively. Sensitivity of the calli to ticarcillin was studied and the responses are analysed with ANOVA. The lowest lethal concentration of ticarcillin was found to be 650 mgl-1. So, concentration below 650 mgl-1 can be used for the successful elimination of Agrobacterium without affecting the regeneration potential of explant. 500 mgl-1 ticarcillin used in this study was observed sufficient for the successful elimination of Agrobacterium without affecting the regeneration potential of calli. For the optimization of parameters affecting transformation, experiments were conducted for the standardisation of optimum concentration of acetosyringone, time of co cultivation, temperature of co cultivation, and suitable Agrobacterium strain. In a study conducted for standardisation of optimum concentration of acetosyringone, increasing number of transformants was obtained with increase in acetosyringone. Significantly higher GUS staining of calli (21.5896) was achieved with the addition of 400μM acetosyringone in the co cultivation media. The effect of number of days of co cultivation on transformation was compared on the GUS expression of 14-day old selected calli. Two-three days of co-cultivation was determined to be the suitable for elephant foot yam because prolonged co-cultivation period (more than three days) was found to promote overgrowth of bacteria and subsequent death of the calli. Correspondingly the transformation percentage was found to decrease with the decrease (less than two days) of co-cultivation period. Investigation of the effect of temperature during co cultivation in elephant foot yam calli revealed that temperature plays an important role in transformation efficiency. Higher temperature, 28°C was found to be optimal to support the highest transient transformation frequency in elephant foot yam and dramatic transient expression reduction occurred when temperature decreased from 22 °C to 20°C. Transformation efficiency with respect to the different strain of Agrobacterium was investigated and the results showed that maximum percent of GUS stained tissue (24.5 percent) of transformants was obtained with the strain LBA4404 with pOYE153 vector followed by AGL0/pOYE153 (14 percent) and GV3103/pCAMBIA 1305.2 (6 percent). GUS assay of transformed callus showed blue colour and confirmation was done by PCR analysis with specific primers and southern blotting. PCR amplification of the DNA of the calli survived in selection medium yielded an expected band size of 280 bp for nptII primer, two bands of size 880bp and 700bp for GUS primer, 300 bp single band for hpt primer and GUSPlus primer. No amplification was obtained for untransformed calli DNA. Nucleic acid spot hybridisation of putative transformants of elephant foot yam further confirmation of the presence of transgene in the DNA. Hybridisation with nptII probe yield spots of varying intensity for all the transformants of AGL0/pOYE153 and LBA4404/pOYE153. Whereas only 5 out of the 8 transformants of GV3103/pCAMBIA1305.2 gave positive for hpt probe and the intensity of spot was low when compared to the spots obtained with nptII probe. Southern hybridisation with DIG labelled nptII probe yield a band for positive control (pOYE153 plasmid) whereas the bands in sample lane was not observed. It is possible that the concentration of DNA (10μl) used in the blot was too low for detection of T-DNA inserts. Hybridisation with hpt probe gave a single band corresponding to the putative transformants lane, which are visible after 30 min exposure indicated that successful hybridisation of the DIG-labelled hpt probe. But the absence of band for positive control was not expected.
Open Access
Identification and characterization of Suppressor of Overexpression of Constans1 (SOC1) gene in Black Pepper (Piper nigrum L.)
(Department of Plant Biotechnology, College of Agriculture, Vellayani, 2016) Manu, K Venu; KAU; Lekha Sreekantan
The present study entitled“Identification and characterization of Suppressor of Overexpression of Constans1 gene in Black Pepper (Piper nigrum L.)”was conducted at the Integrated Biotechnology Block, College of Agriculture, Vellayani, during 2015-2016.The study envisagedisolation and sequencing ofSOC1, a flowering integrator gene in black pepper (variety - Karimunda) and functional characterization of the gene by studying the expression patterns. Degenerate primers were designed for the above said gene based on the gene sequences from NCBI database (SOC1 forward and reverse primers) which were used to isolate and identify the gene. Total RNA of black pepper was isolated using modified CTAB method followed by synthesis of cDNA using AMV RT (Avian myeloblastosis virus reverse transcriptase). PCR (Polymerase chain reaction) with degenerate primers was done using cDNA as the template. However no amplifications were observed after the first reactions. Therefore nested PCR reactions were done using the PCR products of the first reaction as the template. Two bands of size 640 bp and 330 bp were produced in the nested reactions. Sequencing of the product yielded four sequences with each of the sequence showing similarity to the SOC1 gene, when done sequence analysis, thus making it the first flowering integrator gene to be identified in black pepper. Microscopy studies were carried out to see the floral characters of black pepper in detail. Microscopy studies were done using FAA fluid as fixative, sectioning the tissues and staining with safranin and fast green were carried out to see the changes occurring in different development stages of spikes from immature spike to complete spike with berries.
Open Access
Characterization and validation of microsatelite markers for resistance to vascular streak dieback disease in cocoa (Theobroma cacao L.)
(Centre for Plant Biotechnolgy and Molecular Biology, College of Horticulture, Vellanikkara, 2016) Waghmare Sandesh, Tulshiram; KAU; Deepu Mathew
Cocoa is the third important plantation crop next to coffee and tea. The global production and consumption of cocoa is 27.00 lakh MT. Among the fungal diseases, Vascular Streak Dieback (VSD) caused by Ceratobasidium theobromae is the main constraint in cocoa growing countries, causing heavy losses in mature trees as well as seedlings. The VSD disease cannot be effectively controlled by chemicals and hence breeding for the development of resistant varieties is the best strategy to tackle the disease. In order to confirm the transfer of a desired gene into the offspring, conventional breeding methods rely on the field screening which will be highly influenced by the environmental factors. Marker assisted selection is an alternate where the tightly linked molecular markers will be employed to confirm the presence of the gene of interest in the selected plants. Five ISSR and one SSR markers linked to VSD resistance were identified at Kerala Agricultural University (Chandrakant, 2014). The present study was undertaken with the objective of validating the identified SSR and ISSR markers and to characterize the ISSR markers to identify the corresponding SSR markers. For validation and characterization, twenty VSD resistant hybrids and four susceptible clones were used. For molecular analyses, good quality genomic DNA was isolated from twenty four genotypes and ISSR markers UBC 811, UBC 815, UBC 826, UBC 857, UBC 866 and SSR marker mTcCIR 42 were screened. ISSR analysis had shown that all the primers are capable to differentiate resistant and susceptible genotypes. The SSR assay has also differentiated the resistant and susceptible genotypes. The distinct markers generated in resistant genotypes using UBC 811, UBC 826 and UBC 857 were eluted, cloned to pGEMT vector and sequenced. The nucleotide sequences were annotated using BLAST, ORF finder and SSR finder. The BLASTn of UBC811A and UBC811D nucleotide sequence have shown that this resistance locus lie in the chromosome V of Theobroma cacao genome. BLASTn of UBC826A, UBC826B and UBC857 has positioned these loci in chromosome III. ORF1 and ORF3 in UBC811D are shown to code for aflatoxin biosynthesis regulatory protein and NAD(P)H dehydrogenase quinine, respectively. ORF1 in UBC826B and ORF5 in UBC857-2 code for potassium transporter 27 (0sHAK-27) and structural polyprotein precursor of VP2, capsid protein VP2, respectively. All these proteins are identified to have definite roles in defence pathways. The frequency and distribution of SSR motifs, dimmers to decamers, in these ISSR markers and the corresponding primers were identified. The reported ISSR and SSR markers were validated and found to be successful in differentiating resistant and susceptible genotypes of cocoa; thereby these markers can be used in marker assisted breeding for VSD resistance.

Kerala Agricultural University, Thrissur

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