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Open Access
Variability studies in rambutan (Nephelium lappaceum L.)
(Department of Pomology and Floriculture, College of Horticulture, Vellanikkara, 2016) Sameer Muhamed; KAU; Sajan Kurien
Rambutan ( Nephelium lappaceum L.) or ‘hairy litchi’ is an exotic fruit crop with tremendous potential for cultivation in the whole state of Kerala. There exists great variability in rambutan because of the natural cross pollination and seed propagation, which in turn provides great scope for selection. It is in this context that the hundred variable types of rambutan collected from important rambutan growing tracts of Kerala (Pathanamthitta-40, Kottayam-37, Thrissur-18 and Idukki-5) were evaluated for various morpho-physiochemical traits in addition to sensorial perception. The study was taken up with the prime objectives of recording the existing variability and genetic wealth available in order to select and conserve the elite/promising types and thereby, to serve as a basis for promotion of cultivation of this exotic fruit crop in Kerala. The study confirmed that rambutan fruits varied widely in their morpho-physical and biochemical traits such as tree characters, inflorescence characters, fruit characters and quality parameters, which were recorded as per IPGRI crop descriptor. Flowering and fruiting were characters more observed to be a function of the location. The study on phenological growth stages of rambutan according to BBCH scale in different locations opens out a new area on the possibility of staggered fruit production of rambutan in Kerala. The fruits are available from May to October (if cultivated in the humid tropical plains as in Thrissur, Kottayam and Pathanamthitta as well as in the humid sub-tropical belts as in the high ranges of Wayanad), thus making the availability of fresh fruits for nearly half period of a calendar year. With regard to the individual fruit weight, highest fruit weight of 61.5 g was recorded in Col.052 and the lowest fruit weight of 12 g was observed in Col.012 and Col.013. The largest proportionate edible part was found in Col.072 (52%) and the lowest in Col.008 (15%). Free seed aril was found in 19.39 per cent of the collections, while the adherence of aril to seed was medium in 16.33 per cent of the collections. Only 8.16 per cent of the collections produced fruits which could be characterized as very juicy types and 47.99 per cent were grouped as juicy type. About half of the collections (48.97%) had a TSS above 20° Brix. The collections having TSS above 25° Brix (Col.015 with 26° Brix and Col.061 with 27.5° Brix) were classified under the category ‘very sweet’. The titrable acidity and total sugar content ranged from 0.12 to 1.4% and 13 to 18.4% respectively. The loading plot based on tree characters revealed significant positive correlations between rachis length and leaflet width; leaflet width and leaflet length and between tree age and number of leaflets per leaf. Strong positive associations were also observed among fruit characters such as fruit weight, fruit diameter, rind weight, aril weight, aril thickness and spine length. The principal component analysis performed based on tree characters revealed the major contribution of leaflet length, leaflet width and petiole length towards the genetic divergence in rambutan and about 75 per cent of the total variance in fruit characters was mainly determined by the traits such as fruit weight, aril weight, aril thickness, seed weight, seed width, titrable acidity, TSS and sugar content. Clustering of all the three categories of rambutan collections namely elite, export and industrial use types using score plot confirmed the superiority of six collections (Col.021, Col.022, Col.023, Col.052, Col.55 and Col.061) over others, which were selected further for developing a selection criteria in rambutan. In the sensory analysis, Col.061, Col.021 and Col.042 were most preferred/accepted by panelists because of their better fruit weight, taste, juiciness and easy detachment of aril from seed. Two new pests of economic importance (fruit borer, Conogethes punctiferalis and fruit webber, Eublemma anguilifera) have been identified from the rambutan growing tracts of Kerala from fruit set to fruit ripening stage. Their nature of damage and symptoms of infestation have been clearly studied and being reported for the first time in rambutan from India. The study revealed that rambutan selections from Kerala are not only comparable with the best known cultivars in the world, but even excell them. There is an urgent need to standardize the management practices including the varietal wealth in rambutan by using these genetic resources as this crop has already become one of the most treasured fruit particularly as a courtyard crop in Kerala.
Open Access
Evaluation of differential effects of coloured shade nets on selected ornamentals
(Department Of Pomology And Floriculture, College Of Horticulture, Vellanikkara, 2016) Andrew L, Myrthong; KAU; Sudhadevi, P K
Evaluation of differential effect of coloured shade nets on selected ornamentals was undertaken in the Department of Pomology and Floriculture, College of Horticulture, Vellanikkara. Six plant species viz., Nephrolepis exaltata, Asparagus sp. (green leaf type); Spathiphyllum wallisii, Chrysothemis pulchella (flowering type); Tradescantia spathacea „Sitara‟ and Cordyline terminalis (coloured leaf type) were selected for the evaluation. The plants were grown under shade nets of five different colours viz., red, yellow, green, blue and black. Morphological data (both quantitative and qualitative), weather data including temperature, relative humidity, light intensity and PAR (Photosynthetically Active Radiation) were recorded for a period of one year from March 2015 to February 2016. The total chlorophyll and carotenoid contents were evaluated twice, at six and twelve months after planting. The plant growth in terms of height and spread was found to be greatly influenced by red and black coloured nets as the plants under these two nets were the tallest with more spread. Except for Cordyline terminalis, the growth of all plants was the least when grown under blue coloured net. Height and spread of Cordyline terminalis was the lowest under black colour net. Leaf characteristics like area, length and breadth were the highest when grown under black, followed by red coloured nets. The effect of yellow, green and blue coloured nets was not significant. Red net only significantly increased the number of leaves in all plants except Spathiphyllum wallisii, in which it was the highest under blue colour net. The internodal length was the longest in plants under red and shortest under blue coloured nets except in Cordyline terminalis which recorded shortest internodes under black net. Length and girth of petiole of all the plants were more when grown under black net except that of Cordyline terminalis in which it was the longest under red and blue nets.The floral characters of Chrysothemis pulchella were homogeneous under nets of all colours while Spathiphyllum wallisii had bigger flowers with longer stalks under black and red nets. The interval of flower production was the least in red and maximum in plants under blue nets for both the plants. Vase life was studied for those leaves that could be used as cut foliage. No detectable difference in vase life of Asparagus sp. and Spathiphyllum wallisii could be observed. But, leaves of Nephrolepis exaltata had maximum vase life under black and red; medium under yellow and green and minimum under blue nets. The vase life of Cordyline terminalis was minimum under blue net and maximum under all the other net colours which were on par with each other. A higher concentration of total chlorophyll as well as carotenoid were found under black coloured net in all plants except in Spathiphyllum wallisii, in which the maximum concentration was under blue net. The maximum and minimum temperatures and relative humidity were always higher inside the shade nets compared to the open condition. Both light intensity and PAR were reduced inside the shade nets and the reduction was in the ascending order of black, yellow, green, blue and red nets. Overall growth of all the plants was higher under red and black nets, while leaf characteristics were better under black net. Quality wise, the plants under black net overshadowed those under red, yellow, green and blue coloured nets. It was observed that all the plant parameters could not be improved by a single net colour. This study will form a base for future works through which we can draw a clear recommendation on the colour of shade net to be used for obtaining the desired plant architecture which will enhance the commercial value of ornamentals.
Open Access
Variability studies in seedlings of heliconia (Heliconia spp.)
(Department of Pomology and Floriculture,College of Agriculture, Vellayani, 2011) Kadam Darshan, Shashank; KAU; Sheela, V L
Heliconias are one of the important cut flowers of tropics and versatile landscape plants due to their variation in the growth habit and flower characters. The objective of study was to assess the extent of variability among open pollinated seedlings collected from 15 different species and varieties. There was wide variation in the seed characters, germination characters, and morphological characters such as plant height, shoot girth and leaf morphology, leaf area, suckering habit. Also variation in physiological characters such as chlorophyll content, leaf sheath colour of the seedlings was observed. The species Heliconia mariae which registered lowest seed weight was observed to have highest value of plant height. Similarly Heliconia longa which recorded minimum value for seed weight developed in to taller plants. The varieties with smaller seed weight recorded higher germination percent as compared to varieties with higher seed weight. The species Heliconia mariae which recorded the highest plant height, also recorded higher values for leaf length, leaf width and leaf area. The variety Heliconia bihai var. ‘Granda’ registered the lowest plant height, also recorded higher values for leaf length, leaf width and leaf area during the whole observation period. The variety Heliconia latispatha var. ‘Orange Gyro’ recorded highest leaf length: width ratio of 3:1. Among the species and varieties Heliconia bihai var. ‘Granda’ registered the highest number of leaves. Among other leaf characters leaf base was found to have more variation. In species and varieties utilized for study ‘oblique’, ‘cordate’, ‘cuneate’ and ‘obtuse’ type of leaf bases were observed. In heliconia most of the species have distinctive leaf sheath colour pattern. Also presence of powdery coating on back surface of leaves was observed in Heliconia mariae, Heliconia curtispatha, Heliconia pogonantha var. ‘Pogonantha’ and Heliconia longa. The species and varieties showed significant difference in leaf midrib colour. These characters might be identifying feature in some of the varieties. Variation in pigment content was also observed among the species and varieties utilized for study. The variability was high both at phenotypic and genotypic level for most of the characters. PCV was slightly higher than GCV in most of the characters studied. High phenotypic (58.7 %) and genotypic (45.42 %), coefficient of variation was found for number of suckers. High heritability along with high genetic advance was observed for seed weight (heritability 98.05 %, GA 71.72%) and leaf area (heritability 99.96 %, GA 62.95%). The low heritability was recorded for percent of germination and pigment content. The character percentage of germination was found to have significant positive correlation at genotypic and phenotypic level with plant height, rate of shoot elongation, leaf length, leaf width and leaf area. Fourteen species and varieties of heliconia were subjected to D2 analysis based on eight characters. They were grouped into five clusters on the basis of relative magnitude of D2 values. The greater the distance between two clusters, greater is the divergence between the accessions belonging to the two clusters and vice versa. The maximum number of genotypes (5) were included in cluster I, followed by 4 genotypes in cluster II. Three genotypes were included in cluster III. Cluster IV and Cluster V consisted of only one genotype each. Using eucedian distance measures dendrogram was constructed to represent inter and intra specific relationships among the species and varieties. Clustering showed slightly different grouping than grouping by D2 analysis. On drawing a vertical line in the dendrogram along the point corresponding to the similarity coefficient value of 110.12, the 14 species and varieties got divided in to five clusters. The varieties Heliconia lingulata var. ‘Red tip fan’, Heliconia pogonantha var. ‘Pogonantha’ and species Heliconia curtispatha, Heliconia bourgaeana formed the largest cluster. The variety Heliconia bihai var. ‘Granda’ formed separate cluster as like in D2 analysis.
Open Access
Performance of african marigold (Tagetes erecta L.) under different growing conditions
(Department of Pomology and Floriculture, College of Horticulture, Vellanikkara, 2016) Nimisha, Augustine; KAU; Sobhana, A
The experiment entitled “Performance of African marigold (Tagetes erecta L.) under different growing conditions” was undertaken in the Department of Pomology and Floriculture, College of Horticulture, Vellanikkara during the year 2015-2016. Performance of eight African marigold cultivars viz., Sonata Orange, Sonata Yellow, Biocarve Orange, Biocarve Yellow, Local Orange, Local Yellow, Sierra Yellow and Orange Giant were evaluated under open field and rain shelter conditions during two seasons; Season I (from July – November 2015) and Season II (from January – April 2016). Observations were recorded on vegetative, floral and seed characters as well as chlorophyll content in leaves and xanthophyll and flavonoid contents in flowers. The vegetative and floral characters of African marigold cultivars were found to be greatly influenced by the growing conditions and growing seasons. The plant height, internodal length, number of primary branches, number of secondary branches, flower diameter, individual flower weight, number of flowers/plant, shelf life, total flower yield and marketable flower yield were better in the rain shelter grown plants during both the seasons. Stem girth, leaf length, leaf breadth, leaf area and petiole length were the highest in plants grown in open field condition during the two seasons. The highest flower length and pedicel length were recorded in the open field condition during first season and under rain shelter condition during second season. During both the seasons, least number of days for first flowering and 50 per cent flowering were recorded in rain shelter grown plants. Highest seed yield was obtained from plants grown under rain shelter condition, whereas highest seed germination, chlorophyll, xanthophyll and flavonoid contents were recorded in plants grown in the open field condition. Among the cultivars, Orange Giant recorded highest plant height (113.00 cm), internodal length (8.02 cm), number of secondary branches (35.38), flower diameter (6.56 cm), flower weight (12.29 g), total flower yield (668.06 g/plant) and marketable flower yield (606.74 g/plant) during the first season. The cultivar Local Yellow recorded highest seed yield (1.11g) and seed germination (90.00%). Maximum shelf life (4.57 days) was noticed in Sonata Orange. The cultivar Biocarve Orange recorded least number of days for first flowering (43.92 days) and 50 per cent flowering (56.08 days). Highest chlorophyll content was recorded in cultivar Local Yellow, xanthophyll content in cultivar Orange Giant and flavonoid content in Sonata Orange. During the second season, highest plant spread, stem girth (2.47 cm), number of primary branches (8.60), leaf length (12.55 cm), leaf area (13.79 cm2) and seed yield (0.62 g) were recorded in Local Yellow. The cultivar Sonata Orange recorded highest plant height (47.97 cm) and number of secondary branches (22.93). Highest number of flowers/plant (51.27), shelf life (3.17 days), total flower yield (186.43 g/plant), marketable flower yield (182.94 g/plant) and seed germination (89.00%) were recorded in cultivar Orange Giant. The cultivar Biocarve Yellow took least number of days for first flowering and 50 per cent flowering among the cultivars. Highest chlorophyll content was recorded in cultivar Orange Giant, xanthophyll content in cultivar Local Orange and flavonoid content in Sonata Orange. Evaluation of cultivars under open field and rain shelter conditions during both the seasons revealed that, the cultivar Orange Giant was superior to all other cultivars. All the vegetative, floral and seed characters were found to be better during the first season. Even though higher concentration of total chlorophyll was recorded in plants grown during first season xanthophyll and flavonoid contents were maximum during the second season. From the study it is concluded that African marigold can be very well grown under rain shelter condition during July – November, which coincides with the rainy season in Kerala.
Open Access
Morpho-molecular characterization of jackfruit (Artocarpus heterophyllus Lam.) accessions
(College of Horticulture, Vellanikkara, 2015) Aswini, A; KAU; Lila, Mathew K
India is the largest producer of jackfruit in the world (APAARI, 2012). A wide range of genetic and morphological variation has been reported in jackfruit (Ullah and Haque, 2008). In Kerala also rich genetic diversity is reported (Muthulakshmi, 2003; Amma and Kumaran, 2011). Hence it is essential to characterize the accessions at morphological and molecular levels for knowing their identity, genetic relatedness and for exploitation in future breeding programmes. The study on ‘Morpho-molecular characterization of jackfruit (Artocarpusheterophyllus L.) accessions’ was carried out at College of Horticulture, Vellanikkara, Kerala from August 2013 to June 2015. The main objective of the study was to characterise the selected accessions/varieties of jackfruit based on morphological and molecular analysis. Twenty types/accessions of jack fruit maintained in the College orchard and in the Pineapple Research Centre, Vellanikkara along with the Muttom Varikka, Sindoor and Thamarachakka varieties were used for the study. All the accessions/varieties were studied for morphological, physico-chemical and organoleptic properties. Molecular characterization of the selected accessions/varieties was carried out using standard procedure and subjected to ISSR techniques. All the accessions/varieties showed variability in tree characters,inflorescence characters, fruit characters and fruit quality. At the similarity coefficient status of 30 percent, grouping of accessions was done based on tree characters,which resulted in 6 non-overlapping clusters.Tree characters viz.,tree height (4.50 m to 18.00 m), trunk girth (76.00 cm to 270.00 cm), crown shape (pyramidal, broadly pyramidal, spherical, oblong, semi-circular, elliptical and irregular), branching pattern (erect, opposite, verticillate, horizontal and irregular), leaf blade shape (obovate, elliptic, broadly elliptic, narrowly elliptic, oblong and lyrate (wavy)), leaf apex (acute, acuminate, retuse and obtuse) , leaf base shape (oblique, rounded, cuneate and shortly attenuate) , leaf length (12.34 cm to 18.02 cm) and breadth ( 6.37 cm to 9.43 cm) were observed. The accessions were grouped at the similarity coefficient status of 75per cent based on inflorescence characters, which resulted in 5 non-overlapping clusters.Time of flowering, female inflorescence density, female and male inflorescence positions, bearing habit (regular) and secondary flowering (no secondary flowering) were recorded. At the similarity coefficient status of 26 per cent, grouping of accessions was done based on fruit characters, which resulted in 5 non - overlapping clusters. Variation was observed with respect to fruiting season, fruit clustering habit, fruit number (21 to 135) , shape, surface, fruit weight (1.65 kg to 20.00 kg ), fruit yield (41.25 kg/ plant to 1593 kg/ plant), shelf life ( 3 to 5 days ), latex exudation, rind colour and thickness, core length (10.20 cm to 50.50 cm ) and thickness (2.50 cm to 13.90 cm), number of flakes (bulbs) per kg of the fruit (12.61 to 71.15), weight of flake (16.69g to 33.91g), flesh thickness ( 1.26 mm to 7.8 mm), bulb diameter (6.08 cm to 10.11 cm), shape, pulp flavour, colour and consistency, number of seeds (44 to 482), 100-seed weight (240g to 800g) and rind, flake and seed ratio (2.30 to 7.31). Sensory evaluation viz.,taste, flavour, colour, texture, sweetness and appearance were recorded on basis of 9 point hedonic scale. At the similarity coefficient status of 7 per cent, grouping of accessions was done based on biochemical characters, which resulted in 14 non - overlapping clusters.The percentage of moisture (29 to 74 %), TSS (20.30 0 Brix to 33.80 o Brix), reducing sugars (6.61 to 13.16 %) and non-reducing sugars (5.16 to 13.29 %) and β carotene (0.99 to 12.94 mg/100g) were estimated. In molecular characterization five main clusters were formed at 77 per cent similarity. The first cluster grouped four accessions (Acc. 1, Acc. 3, Acc. 5, Acc. 4). The second cluster consists of Sindoor. Third cluster consists of Thamarachakka, fourth cluster consists of Acc. 2 and MuttomVarikka and the fifth cluster consist of five accessions (Acc. 15, Acc. 17, Acc. 18, Acc. 19, and Acc. 16). First cluster included the firm fleshed jackfruit accessions whereas Cluster V included all the soft fleshed accessions. Thus in the present investigation, evaluation and characterization of twenty accessions and three varieties namely Sindoor, Muttom Varikka and Thamarachakka have been made to understand the extent of genetic diversity and similarity with the help of morphological, biochemical and molecular characters for identifying superior types for further selection. Sindoor and Muttom Varikka are the two firm fleshed varieties widely accepted in Kerala and suited for homestead cultivation. The morphological and fruit quantity and quality parameters of accessions 1, 3, 5, 7, 10, 14 and 15 are compared with the above varieties. But for specific purposes, desirable traits are to be employed for selection. Further studies are also required to confirm the results. Molecular markers - ISSR markers could be successfully employed in determining the texture of the jackfruit flakes (firm/soft flesh types) and also for knowing the genetic relatedness.
Open Access
Evaluation of vanda orchids for commercial traits
(College of Horticulture, Vellanikkara, 2015) Minnu, Sebastian; KAU; Geetha, C K
The investigation on the evaluation of Vanda orchids was conducted at the Department of Pomology and Floriculture, College of Horticulture, Vellanikkara, during 2013-‘14 with the objective of evaluating the field performance for commercial exploitation. Thirty Vanda varieties/ hybrids were selected for the study. They were evaluated for their height, spread, shoot characters (nature, girth, internodal length), leaf characters (length, breadth, area, number, interval of leaf production, leaf sheath characters), root characters (length, girth, number), floral characters (days from spike emergence to opening, longevity of spike, interval of spike production, annual production of spike, blooming period, number of florets per spike, individual flower life, flower size, features of petal, lip and column) under field conditions, as well as post harvest parameters (spike longevity, number of buds opening in vase, physiological loss in weight, water uptake and floret span). The varieties exhibited wide variation in both vegetative and floral characters. Maximum plant height was observed in V. Pompimol and the minimum in V. Thailand Beauty. V. Kasem’s Delight x V. Bitz’s Heartthrob recorded the maximum plant spread and V. Pachara Delight Pink the minimum. Shoot girth and internodal length were the maximum in V. Taweesuksa x V. Kultana Gold x V. Green Gold and V. Pakchong New Land x V. Annette Jones, respectively while the minimum was recorded by V. Varuvathe Pink and V. Thailand Beauty, respectively. Leaf number was maximum in V. Prapawan and the minimum in V. Apec Blue. Leaf length as well as leaf area were the maximum in V. Pompimol, whereas the least values for these characters were for V. Prapawan and V. Anek Delight, respectively. V. Lumpini Red x V. Taweewan recorded the maximum leaf breadth and V. Fuchs Delight, the minimum. Interval of leaf production was the maximum in V. Katsuura x V. Fuchs Delight and the least in V. Lumpini Red x V. Taweewan. Among the vanda varieties, V. Apec Blue recorded, the maximum number of roots whereas V. Anek Delight and V. Lumpini Red x V. Taweewan had maximum root length and girth, respectively and the minimum was in V. Varuvathe Pink, V. Urbchitr x V. Bitz’s Heartthrob and V. Dr Anek x V. Bitz’s Heartthrob, respectively. The duration from spike emergence to opening of florets was the maximum in V. Urbchitr x V. Bitz’s Heartthrob. Time required for opening florets (first and 50%) was the least for V. Apec Blue and V. Anek Delight, respectively. Spike longevity was the maximum for V. Madame Rattana and the minimum for V. Anek Delight. Interval of spike production was the maximum in V. Pompimol and the minimum in V. Pranermprai x V. tessellata. Accordingly, annual spike production was the minimum in V. Pompimol and it was the highest in V. Pathum Gold. Spike characters, like length was maximum in V. Kultana Delight Red, while girth in V. Urbchitr x V. Bitz’s Heartthrob .The rachis length and number of florets were the maximum in V. Thailand Beauty and the minimum in V. Varuvathe Pink. The internodal length between florets was the maximum in V. Prapawan and the minimum in V. Red Gem. Lip length and flower size recorded the highest values in V. Pompimol whereas column length was the highest in V. Dr Anek x V. Mimi Palmer. All these characters were the lowest in V. Red Gem. The life of individual floret on the spike was the maximum for V. Katsuura x V. Fuchs Delight and the minimum in V. Pakchong New Land x V. Annette Jones. Among the post harvest characters, spike longevity (vase life) was the maximum in V. Katsuura x V. Fuchs Delight followed by V. Thailand Beauty and the minimum in V. Lumpini Red x V. Taweewan. The life span of each floret was also high in V. Katsuura x V. Fuchs Delight. The qualitative characters of vanda varieties/hybrids differed in all aspects. The leaves were channelled, smooth, rigid and green coloured, with no pigmentation. Three types of leaf apex, viz., tridentate, praemorse and emarginate were observed. The leaves were arranged alternately and were oriented as straight or horizontal with an arching tendency. Varying petal shapes and curvatures were observed. The petal margin was undulated in most of the cases and rarely entire. Uniform, spotted as well as blotched colour patterns were seen in the petals. Lip-lobe shapes and lip curvature were varying in the varieties. Lip apex was bilobed in most cases; acute or truncate apices were also noticed. Lip surface was glabrous, usually single or double coloured whereas it was triple coloured in V. Pathum Gold and V. Robert’s Delight. Lip colour pattern was uniform or streaked or spotted. The column colour pattern was uniform, streaked, blotched or spotted. Spur type was found to be cylindrical in most varieties and saccate in some. The variety V. Pranermprai x V. tessellata possessed good fragrance. Considering the overall quantitative and qualitative parameters, V. Pathum Gold, V. Lumpini Red x V. Taweewan, V. Pachara Delight Pink, V. Apec Blue, V. Prapawan, V. Urbchitr x V. Bitz’s Heartthrob and V. Thailand Beauty were excellent, both for cut flower production and as pot plants. V. Pranermprai x V. tessellata and V. Katsuura x V. Fuchs Delight have more potential for use as cut flower whereas V. Red Gem and V. Anek Delight were excellent as pot plants.
Open Access
Performance evaluation of turf grass species in the humid tropics
(College of Horticulture, Vellanikkara, 2014) Abdul, Raziq; KAU; Valsalakumari, P K
The present study entitled “Performance evaluation of turf grass species in the humid tropics” was carried out at the Department of Pomology and Floriculture, College of Horticulture, Vellanikkara from January 2012 to August 2013. The objective was to evaluate the performance of turf grass species with respect to growth, establishment rate and tolerance to biotic and abiotic stresses in order to introduce new grass species for the tropical lawns. Ten turf grass species, viz., Cynodon dactylon, Stenotaphrum secundatum, Zoysia japonica, Paspalum notatum, Eragrostis curvula, Cynodon dactylon 419, Poa pratensis, Lolium perenne, Agrostis palustris, Dichondra micrantha were selected for the study. The first four species were local and the remaining six were imported from the USA. Three species, viz., Poa pratensis, Lolium perenne and Agrostis palustris did not establish and hence further studies were carried out on the remaining seven. Besides the studies in the open field condition, their tolerance to shade and air pollution were also evaluated. The experiment was laid out in CRD for shade tolerance studies and RBD for open field condition with three replications. Various vegetative and qualitative characters were recorded and data were statistically analysed. The maximum duration for total coverage of the area was recorded by Paspalum notatum (189 days) and the minimum by Eragrostis curvula (100 days). There were significant differences for plant height and shoot length in shade and open field conditions. Leaf length, leaf width, leaf texture, leaf colour and arrangement of unfurled leaves were recorded and were used for categorizing the species. Based on leaf width, plants were categorized into fine, coarse and medium coarse textured. Leaf colour was categorized as light, medium and dark green. According to arrangement of unfurled leaves, they were classified as rolled and folded. Root characters were recorded in terms of number, length and root shoot ratio. Growth habit was recorded as spreading and upright. Response of different turf grass species to mowing was recorded in terms of time taken for first mowing, relative mowing height, weight of biomass removed at first mowing, recuperative ability, frequency of mowing and mowing tolerance. The maximum duration for first mowing was recorded by Dichondra micrantha (174.7 days) and the minimum by Eragrostis curvula (57.7 days). The later showed the highest value (3330.7g) for biomass and the minimum (30.0 g) was by Zoysia japonica. Relative mowing height in open field condition was recorded as low in Cynodon dactylon 419 and Zoysia Japonica, medium for Dichondra micrantha and Cynodon dactylon and high in Paspalum notatum, Eragrostis curvula and Stenotaphrum. Recuperative ability was poor in Dichondra micrantha, Paspalum notatum and Eragrostis curvula and high in Cynodon dactylon 419 and Cynodon dactylon. Mowing frequency was less in Dichondra micrantha, Cynodon dactylon 419, Zoysia japonica and Stenotaphum secundatum. It was more in Paspalum notatum, Eragrostis curvula. Mowing tolerance was low in Dichondra micrantha, Paspalum notatum and Eragrostis curvula whereas it was high in Cynodon dactylon 419, Cynodon dactylon, Zoysia japonica. Response to mowing followed the same pattern under various shade levels also. Air Pollution Tolerance Index of Dichondra micrantha was the highest (24.8) and the lowest value (8.35) was observed for Cynodon dactylon. Turf grass species were categorized into sensitive (value ≤ 14), intermediate (15-19), medium tolerant (20-24) and tolerant (>24). All the species, except Dichondra micrantha, was sensitive to air pollution. Major pests observed were, leaf eating caterpillars (army worm) in Paspalum notatum and Eragrostis curvula and termites in Dichondra micrantha, Zoysia japonica, Cynodon dactylon 419, Eragrostis curvula, and Paspalum notatum. Rats were another problem in turf area. No serious disease was observed except the gray leaf disease, caused by Pyriculari grisea which was found in Stenotaphrum secundatum.Weeds affected the turf growth seriously, both under shade and in open field conditions. The important weeds were Alloteropsis cimicina, Ageratum conyzoides, Lindernia crustacean, Cyperus iria, Cyperus rotandus , Digitaria bicornis, Synedrella nodiflora, Mimosa pudica and Desmodium triflorum. Among the turf grass species evaluated under open field condition Cynodon dactylon 419, Cyndon dactylon, Zoysia japonica, Stenotaphrum secundatum and Paspalum notatum were suitable for lawn under humid tropical condition. Eragrostis curvula, though not suitable as a turf grass, can be grown in pots and also as an edge plant. Among the turf grass species evaluated under various shade levels (0%, 25% and 50%) Dichondra micrantha, Zoysia Japonica and Paspalum notatum performed better under 25 per cent and zero per cent shade levels and Stenotaphrum secundatum at the shade levels tried.
Open Access
Enhancement of spike qualities of gladiolus (Gladiolus grandiflorus L.)
(College of Horticulture, Vellanikkara, 2015) Simmy, A M; KAU; Lila, Mathew K
The studies on ‘Enhancement of spike qualities of Gladiolus (Gladiolus grandiflorus L)” were conducted during 2012-13 in the Department of Pomology and Floriculture, College of Horticulture, Vellanikkara, in two seasons, from May 2012 to October 2012 (first season) and from November 2012 to April 2013 (second season). The objectives were to compare the performance of gladiolus varieties under open and rain shelter conditions and to standardize the post harvest treatments to improve the spike qualities. The three gladiolus varieties namely Oscar, Summer Sunshine and White Prosperity, were grown as per KAU recommendation, both in open field and rain shelter. Detailed observations were made on growth, flowering and post harvest characters. The study clearly indicated that growing condition, season and genotype had significant influence on vegetative as well as floral characters of gladiolus. The vegetative characters like plant height, number of leaves and leaf area were noticed to be better in rain shelter grown plants, during both seasons. Early spike emergence [Oscar (S1- 87.35 days, S2- 73.25 days), Summer Sunshine (S1- 61.90 days, S2- 56.22 days) and White Prosperity (S1- 72.05 days, S2- 62.08 days)], shorter duration from spike emergence to opening and longer blooming period [Oscar (S1- 9.03 days, S2-10.08 days), Summer Sunshine (S1- 11.68 days, S2-13.03days), and White prosperity (S1- 9.68 days, S2-12.05 days)] were noticed in rain shelter grown plants. Total duration of the crop was shorter in rain shelter during both seasons. Spike length, spike diameter, rachis length, number of florets per spike [Oscar (S1-10.35, S2-12.00), Summer Sunshine (S1-11.38, S2- 13.80) and White Prosperity (S1-9.23, S2- 11.57)], floret size and number of florets opened at a time were observed better in rain shelter grown plants, during both seasons. Vase characters were also found to be superior in rain shelter grown plants. Rain shelter grown plants of Oscar (S1-5.00 days, S2-6.00 days), Summer Sunshine (S1-6.67 days, S2- 8.67 days) and White Prosperity (S1-3.3 days, S2- 4.00 days) recorded significantly more vase life, during both seasons. Corm yield recorded were maximum in plants grown in rain shelter. Cormel yield recorded was maximum in rain shelter for Oscar and White prosperity where as for Summer Sunshine, maximum cormel yield was observed in open field. Among the varieties, Summer Sunshine had better performance with respect to most of the vegetative, spike and vase characters, compared to other varieties, both in rain shelter and open field. Oscar recorded relatively higher floret size ( S1-9.47 cm, S2-10.31 cm) as well as cormel yield ( S1- 14.71, S2- 21.63) compared to other varieties, during both seasons in both growing conditions. The results showed that spike qualities as well as corm yield can be enhanced by rain shelter cultivation. It was also noticed that November planting was found to be better than May planting, in order to obtain quality spikes as well as good corm yield in gladiolus under Vellanikkara conditions. For post harvest studies, gladiolus spikes were harvested when the first floret showed colour. Spikes were subjected to the post harvest treatments - pulsing, holding, storage and packing. Among the pulsing solutions Sucrose 20% + 8 HQC 200 ppm was found to be better than other treatments for all the varieties, with respect to percentage of fully opened florets , percentage of unopened florets, longevity of individual florets (Oscar -1.8 days, Summer Sunshine – 3.8 days and White prosperity- 2.25 days), number of florets opened at a time, water uptake and vase life.For all the varieties, holding solution of Sucrose 5% + AgNO3 50 ppm was found to record the maximum percentage of fully opened florets, longevity of individual florets, water uptake and vase life (Oscar -7 days, Summer Sunshine - 9 days and White prosperity- 7days). Maximum percentage of fully opened florets, longevity of individual florets, water uptake and vase life were observed in spikes stored at 80C, for all the varieties. The spikes packed in polypropylene sheet exhibited the highest percentage of fully opened and partially opened florets, longevity of individual florets, number of florets opened at a time, water uptake and vase life (Oscar-9 days, Summer Sunshine- 9.75 days and White prosperty- 8 days). Nature of spike bending of all the varieties was not significantly influenced by pulsing and holding solutions, packing and storage. The post harvest studies revealed that pulsing of gladiolus spikes with sucrose 20 percent and 8- HQC 200 ppm for 3 hours, packing with polypropylene sheet, storing at 80C for 24 hours and holding in Sucrose 5% + AgNO3 50 ppm solution can significantly improve the vase characters of gladiolus.
Open Access
Performance of strawberry (Fragaria x ananassa Duch.) in different growing conditions
(College of Horticulture, Vellanikkara, 2015) Anu Kurian; KAU; Ajith Kumar, K
The study on “Performance of strawberry (Fragaria x ananassa Duch.) in different growing conditions” was conducted at College of Horticulture, Vellanikkara, Thrissur and Krishi Vigyan Kendra, Ambalavayal, Wayanad, Kerala from September 2013 to March 2014. The main objective was to compare the performance of strawberry (Fragaria x ananassa Duch.) under three growing conditions (open field, greenhouse and fan and pad system) and under two agro ecological zones of Kerala (Central mid-lands and High ranges). Among the growth characters, plant height and plant spread were maximum in the fan and pad system in Central midlands. More number of leaves per plant was recorded under open condition. Number of leaves and plant spread were the maximum with planting in the last week of September. In High ranges, plant height and plant spread were highest in the greenhouse system and maximum number of leaves was recorded in open condition. Number of leaves per plant recorded was maximum in last week of September planting. In Central mid-lands, minimum days to first flowering (55.67 days) was recorded under fan and pad system. The systems of growing had no effect on number of flowers and number of clusters per plant. Days to first flowering was minimum (57.11 days) in plants mulched with black polyethylene. Early flowering (55.0 days) was observed when mulched with black polyethylene in fan and pad system. In High ranges, number of flowers (20.78) and number of clusters per plant (17.47) were highest under open condition. Systems of growing had no effect on days to first flowering. Plants in the open condition with black polyethylene mulch resulted in maximum number of flowers (25.85) and number of clusters per plant (21.57) per plant. Among the yield attributes, in Central midlands, fan and pad system was the best with respect to production of fruits per plant (5.87). Systems of growing had no effect on yield and average fruit weight per plant. Greenhouse was the best with respect to early harvest (82.67 days) of fruits whereas harvesting priod extended up to 163.25 days under open condition. Planting in last week of September recorded maximum number of fruits per plant (5.43). Early harvest (95.06 days) was recorded when mulched with black polyethylene. In High ranges, maximum number of fruits (8.97), yield (80.35 g), average fruit weight (8.79 g) per plant and early harvest of fruits (81.17 days) were observed in open condition. Maximum number of fruits (10.53) and highest yield (102.17 g) per plant were recorded in plants with black polyethylene mulch under open condition. In Central midlands, systems of growing had no effect on content of total soluble solids (TSS), acidity, TSS/acidity ratio. Highest total sugars (6.03%) was recorded in open condition. Time of planting and mulch had no effect on quality parameters. In High ranges, lowest acidity (0.13 %), highest TSS (11.07 0 Brix), TSS/acidity ratio (86.46) and total sugars (5.88 %) were recorded under greenhouse condition. In Central mid-lands, the overall sensory score was highest in plants in the open field which were planted in the last week of September with white mulch. However, in High ranges, the overall sensory score was highest in open filed, planted in last week of September with black polyethylene mulch. The fruits harvested from High ranges had better appearance and colour compared to fruits obtained from Central midlands.

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