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ThesisItem Open Access Growth and productivity as function of site quality and age in teak plantations of Nilambur, Kerala(Department of Silviculture and Agroforestry, College of Forestry, Vellanikkara, 2022) Sankar Thampuran, M V; KAU; Kunhamu, T KTeak has been one among the principal timber species widely used across the world due to its matchless combination of qualities. Kerala has around 76,710 ha of pure teak and 14,440 ha of teak with softwood plantation making up 49.08 and 9.24 per cent respectively of the total plantation area in the state. Despite having the largest share of plantations under teak, the productivity of teak plantations of Kerala are under serious decline and has been a matter of concern in the scientific parlance. Evidences suggest that even in Nilambur, the celebrated land of teak, there has been large scale decline in productivity of teak plantations. However, quantitative aspects of the productivity of teak and the drivers of changes especially in the best teak growing region in Kerala such as Nilambur, is lacking. In this backdrop, a field study entitled “Growth and productivity as function of site quality and age in teak plantations of Nilambur, Kerala” was conducted in selected plantations from Nilambur North and Nilambur South Forest Divisions. The plantations were selected based on the information available from Kerala Forest Department on their age and site quality. Four site qualities (SQ I, SQ II, SQ III and SQ IV) and five age classes (10-20, 20-30, 30-40, 40-50 and 50+) were considered for the study forming a total of 20 plantations (4 site qualities x 5 age classes = 20 plantations). Five sample plots, each of size 24m x 24m were laid out randomly in each of the selected plantations and parameters like total tree height, bole height, diameter at breast height, diameter at crown point and crown width were measured in the field. Also, soil sampling was done in four plantations of different site qualities falling in the mature age class of 40-50. For this, 1 m deep soil pits were dug, one each inside the plantation and in the respective contiguous treeless open. Sampling was done in five depth intervals (0-20, 20-40, 40-60, 60- 80 and 80-100 cm). Thus, a total of 120 samples of soil were collected for analysis. The collected soil was analysed for physical properties like bulk density and particle size distribution/ texture and chemical properties like pH, total Nitrogen, organic Carbon content, available Phosphorus and exchangeable Potassium following standard procedures. 122 The results showed that among the plantations studied in Nilambur, the SQ I plantations showed dominance in all growth parameters of teak while a predictable pattern of change was lacking across the subsequent site qualities. There was large heterogeneity among the plantations in terms of management that had a confounding effect on the potential exploitation of the site resources for optimal growth of teak. Many of the plantations had high density of invaded miscellaneous trees which have increased the effective density and seriously affected the growth of teak. The density of miscellaneous trees varied from 0 to 694 trees per hectare among the studied plantations. The competition with miscellaneous species has created large scale variability within each stand in growth attributes. Normal distribution of diameter classes was observable in the plantations studied due to high effective density. Stand density being a critical factor that decide productivity and product quality in teak plantations, the observed variability in productivity could be attributed to poor adherence to proper density regulation. Also, the productivity of the plantations has been considerably influenced by poor adherence to timely plantation management practices. The Mean Annual Increment varied from 0.56 to 8.70 m3ha-1yr-1 among all the plantations studied. On comparing with the All-India yield table for teak, the plantations showed growth and productivity estimates that were quite different from their assigned site quality. In the age class 40-50, the SQ I plantation showed a height that was corresponding to SQ III according to the yield table, while the SQ IV plantation height corresponded to the SQ II. All the observed soil parameters with in the experimental plots were well within the range required for the optimal growth of teak. However, except for SQ1, we could not observe any predictable change in soil properties across the remaining site qualities. The Bulk density of soil increased with depth, both inside and outside the plantations. The rate of increase of bulk density was higher in the treeless open areas compared to the plantations. Th soil texture remained as sandy loam or loamy sand for all the analysed soil samples. The soil pH varied from 5.17 to 5.98 between the soil samples that were analysed. The organic Carbon content in various layers of plantation soil varied from 0.58 to 2.07 %. Total Nitrogen varied from 0.077 to 123 0.223 %. Available Phosphorus varied from 2.10 to 17.33 kgha-1. Exchangeable potassium varied from 51.82 to 488.30 kgha-1. Attempts to relate the soil properties with the site productivity could not derive meaningful correlations suggesting that the productivity decline might be an effect of poor management rather than depletion of nutrient status. The study suggests that there is an urgent need to revisit and reassess the site quality of the plantations in Nilambur and to give utmost concern for adhering to scientific stand management in timebound manner for deriving optimal productivity from teak plantations of Nilambur.ThesisItem Open Access Evaluation of biodegradable containers for seedling production in tree nurseries(Department of Silviculture and Agroforestry ,College of Forestry, Vellanikkara, 2020) Subhasmita, Parida; KAU; Kunhamu, T KA nursery trial titled ‘Evaluation of biodegradable containers for seedling production in tree nurseries’ was conducted to develop alternate eco-friendly plant container as substitute for conventional polythene bag based containers at College of Forestry, Kerala Agricultural University, Thrissur. The study involved a three month long preliminary trial to explore the efficacy of various locally available materials for use as container for tree species. Based on the preliminary trial, five better performing container types were screened for detailed nursery trial to further examine their efficiency as containers for tree seedling production. Teak (Tectona grandis) being the widely produced forest planation species in Kerala, the nursery trials were performed with teak as test crop. The locally available materials used as containers for the preliminary trial included cow dung pot, sugarcane bagasse, arecanut sheath, mud pots, bamboo splits, bamboo basket, coco pot, cloth bag, nonwoven bag, bioplastic bag and treated card board. The containers were evaluated for their durability, physical stability to management practices such as irrigation and manuring, survival percent, height and collar diameter of the teak seedlings. It was observed that the bamboo splits based containers had the highest durability and can be used for two seasons while containers made from arecanut sheath, cow dung pot, sugarcane bagasee pot, bamboo basket, bioplastic bag and cloth bag totally degraded within two months suggesting their unsuitability for tree seedling production. In general, the better container types in terms of overall seedling growth performance and physical soundness were nonwoven bag, bamboo split, coco pot, treated cardboard pot and mud pot. These five container types along with coir root trainer (CRT) supplied by Kerala Forest Department were subjected to detailed nursery trial. It was observed that considerable variability existed in seedling growth characters such as height, collar diameter, number of leaves, leaf area, number of secondary and tertiary roots, lateral root length, root length: shoot length ratio, root and shoot dry and total dry weight. Among all container types studied, nonwoven bag grown seedlings showed better growth performance followed by seedlings grown in bamboo split containers while mud pot raised seedlings showed the lowest performance during all the stages of seedling growth. The overall performance of the container types followed the order: nonwoven bag > bamboo split > coco pot > treated cardboard > Coir root trainer (CRT) > mud pot. The cost of production per seedling was Rs 8.3 for non-woven bag, Rs 60.2 for coco pot, Rs 62.0 for mud pot, Rs 11.0 for bamboo split, Rs 12.8 for treated cardboard pot and Rs 25.8 for Coir root trainer (CRT). The Benefit: Cost ratio of raising 3- month old teak seedling ranged from 0.32 – 2.45. The value was highest for seedlings raised in bamboo split pot (2.45) followed by nonwoven bag (2.41) and cardboard (1.56) while it was less than one for all the remaining container types. The trial suggest that further studies are required to develop protocols for the reinforcement of biodegradable containers for increased phys ical strength and durability.ThesisItem Open Access Floristic diversity and regeneration status of moist deciduous forests in Thrissur district, Kerala :reassessment after three decades(Department of Silviculture and Wildlife Science, College of Forestry, Vellanikkara, 2020) Abhi, Jamatia; KAU; Kunhamu, T KMoist deciduous forests in Kerala constitute one of the most degraded forest ecosystems consequent to demographic pressure and other bio- physical factors. Field investigation was carried out to study the changes in phytosociology and vegetation dynamics of Moist Deciduous Forests in selected locations in Thrissur Forest Division, Kerala during 2018-19. The primary objective of the study was to assess the changes in floristic diversity, structure and regeneration status of moist deciduous forests compared to a similar study carried out in the same locations prior to three decades. The selected three locations were Karadippara and Kalluchal in Peechi WL sanctuary and Kuthiran in Pattikkad range. The vegetation attributes subjected to detailed assessment included species diversity, density, relative density, basal area, relative basal area, relative frequency and Importance Value Index and size class distribution of vegetation. A total of 51 species have been reported in various study locations in the Moist Deciduous Forests of Thrissur Forest Division. Kalluchal represented the highest number of woody species (48 species) followed by Karadippara (37 species) and Kuthiran recording the lowest with 26 species. Tree density showed profound variation across sites with Kalluchal giving the highest number (691 stems ha-1) followed by Karadippara (688 stems ha-1) and lowest for Kuthiran (516 stems ha-1). Xylia xylocarpa contributed the maximum number of stems in all the three sites followed by Wrightia tinctoria and Holarrhena antidysentrica. Mean relative density was highest for upper stratum (44.62%) and 33.07% for the lower stratum and lowest for the middle stratum (22.30%). Karadippara, Kalluchal and Kuthiran sites represented 30, 45 and 20 species within frequency class I (within 1-20%) and there was conspicuous absence of species in the higher frequency class in all the three sites. All the three sites had similar total IVI around 300. The major share of the IVI was confined to the species in the upper stratum (58 to 60%) while the middle and lower stratum has a lower and similar trend in IVI distribution (20% each). Size class distribution of among various social l classes ii showed conspicuous absence of majority of tree species in the higher size class suggesting a skewed distribution pattern. Almost 85% of individuals in each species belonged to lower size classes (h50 and h100) which drastically declined with increase in size class. A comparison with the study in the same sites three decades back indicates variable results. There was overall improvement in species diversity and phyto-sociological attributes in the Kalluchal region particularly, the species density and regeneration patterns. However, the number of individuals in the present study at Karadippara and Kuthiran sites, especially in the lower size classes were far lower compared to the previous study implying that the regeneration patterns of many tree species have been seriously affected by the undesirable changes in the past three decades. Probably, apart from human influences, the impact of changing climate may also have affected the regeneration ecology and vegetation dynamics of the MDF forests in Thrissur District which necessitate further detailed investigation in this line.ThesisItem Open Access Impact of seed priming techniques on germination and seedling performance in sandal (Santalum album L.)(Department of Silviculture and Agroforestry, College of Forestry,Vellanikkara, 2019) Chithra, P; KAU; Jijeesh, C MSantalum album L, known as the East Indian Sandalwood is a semi-root parasitic tree native to South India and it is one of the most precious and valuable among Indian forest trees. The poor rate of germination coupled with long germination period is the major constraints in the regeneration of sandal. Present study was conducted to assess the impact of seed priming techniques on the germination and seedling growth attributes of sandal at College of Forestry, Vellanikkara, Thrissur. The effect of different duration and concentration of priming agents viz. water (Hydropriming for 3, 6, 9 and 12 days), Pseudomonas fluorescens (Biopriming at 25, 50, 75 and 100% for 2, 4, 6 and 8 days), Polyethylene Glycol 6000 (Osmopriming at 5, 10, 15 and 20% for 3, 6, 9 and 12 days) and MnSO4 (Chemical priming at 0.4, 0.6, 0.8 and 1.0 M for 3, 6, 9 and 12 days) on seed germination and subsequent seedling growth in sandal were studied. The non- primed seeds were kept as control. Primed seeds were stored for one day and one month after the completion of priming processes and the germination and seedling growth were observed. The germination was obtained only in the seeds stored for one day after priming process and the seeds stored for one month failed to germinate. Results indicated that the hydropriming of the seeds could not improve the germination of the sandal seeds compared to control. Biopriming significantly increased the seed germination and the highest germination percentage (88%) was recorded in the seeds subjected to biopriming for 8 days at 100% concentration, which was 1.9 times higher compared to control. The highest germination recorded in osmopriming was 78%. The chemical priming with MnSO4 at different concentrations for 3 days also recorded the higher germination (88%) comparable to biopriming. Electrical conductivity was the highest in the leachates of seeds hydroprimed for 12 days (1.96 dS cm-1) and was the lowest in seeds subjected to biopriming (0.03 dS cm-1). The leachate conductivity of the seeds subjected to osmopriming treatments (1.69 dS cm-1) was comparable to that of the hydropriming treatments. Although the different concentrations and duration of MnSO4 reduced the leakage of solutes from the sandal seeds, the electrical conductivity was higher than that of the biopriming treatments. Hence, biopriming treatments were the best in reducing the leakage of solutes from the cells leading to better membrane integrity and stability. Biochemical analysis of the primed and non-primed seeds indicated that the hydropriming treatments recorded significantly lower carbohydrate, protein and crude fat content compared to control.ThesisItem Open Access Productivity of tree fodder banks in selected homegardens of central Kerala(Department of Silviculture and Agroforestry, College of Forestry, Vellanikkara, 2019) Anush Patric; KAU; Asha, K RajThe field study entitled “Productivity of tree fodder banks in selected homegardens of Central Kerala” was carried out as three separate experiments in selected small, medium, and large scale homegarden with livestock component in Arimboor panchayath, Thrissur, Kerala during 2018-2019. The study aimed to assess the forage yield and nutritive value of five fodder tree species viz. Mulberry (Morus indica), Agathi (Sesbania grandiflora), Moringa (Moringa oleifera), Gliricidia (Gliricidia sepium) and Calliandra (Calliandra calothyrsus) under hedgerow planting (45 x 45 cm spacing) in homegardens; and to explore the short term changes in soil nutrient status of homegardens with tree fodder integration. The treatments were laid out in randomized block design replicated four times. The trees were harvested at 1m height and at the interval of two months during rainy season and three months during summer season The result revealed that all the tree species established well in the homegardens after planting. Initial growth of Agathi and Calliandra was faster in terms of plant height, whereas Gliricidia showed excellence in lateral branching. In general, coppice parameters were better for Gliricidia followed by Agathi and Calliandra. The annual green and dry forage yields were higher for Gliricidia (24.27 & 4.39 Mg ha-1) and Calliandra (16.38 & 4.60 Mg ha-1) respectively followed by Agathi and Mulberry. The yield from Moringa was comparatively poor. Seasonal fodder yields were higher for rainy period than summer. Forage quality also differed among tree species. Calliandra (22.57 %) and Gliricidia (19.99 %) fodder had more crude protein content and yield followed by Mulberry (16.74 %). Crude fibre content was lower in Gliricidia, Calliandra and Mulberry than other species. Mulberry (7.93 %), Moringa (7.61 %) and Agathi (7.12 %) had higher ash content, whereas Moringa and Mulberry had higher P and K content. Dry matter content was significantly higher for Calliandra (30.40 %) and Mulberry (28.73 %). Higher leaf-stem ratio was observed in Mulberry (2.09) and Gliricidia (2.05), followed by Calliandra (1.67). In general, Gliricidia and Calliandra had higher forage yields and protein content, followed by Agathi. Mulberry showed intermediate performance with respect to yield and quality. Moringa was inferior in forage yields but rich in quality attributes like ash, minerals and P content. Comparing homegardens, yield performance of fodder banks was higher in medium homegarden (MHG) followed by large (LHG) and small homegarden (SHG). Whereas reverse trend was observed in quality attributes of fodder. Survival count of the trees after one year of planting was significantly higher in Mulberry (80.06 %) and Calliandra (71.13 %), followed by Gliricidia (44.35 %), whereas survival was drastically lower for Agathi (31.55 %) and Moringa (31.55 %). Inspite of poor yields of Mulberry in the initial year, higher persistence of Mulberry indicates its better performance in the subsequent years. Comparing different homegardens, survival percentage was higher for SHG (59.47 %) and MHG (54.46 %) followed by LHG (41.07 %). Low survival in LHG was due to waterlogging during rainy season. In general, the soil organic carbon, N and P content improved with fodder tree integration in SHG and MHG. There was no visible changes in K content. Soil N and P levels also improved in LHG whereas SOC showed a declining trend. Comparing tree species, Agathi plots showed more soil improvement with higher SOC and NPK levels whereas soil depletion was more evident in Moringa with respect to carbon, P and K, and in Calliandra in terms of carbon and nitrogen. PAR transmittance ranged from 50.10 % in SHG to 52.75 % in MHG and LHG which were on par. PAR transmittance levels in various tree plots ranged from 45.50 – 58.57 % with no statistical significance. A marginal reduction in transmittance was observed in Mulberry (45.50 %) when compared to other species. The economics of fodder bank cultivation in homegardens varied significantly with respect to tree species. Gliricidia fodder banks generated higher returns and B: C ratio (1.28) whereas all other species showed B: C ratio of less than one. The initial cost for raising fodder banks in homesteads is high whereas the forage yield in the initial year of planting is comparatively less as trees are under the establishment phase. Hence, in conclusion, fodder trees like Gliricidia, Calliandra, and Mulberry with good yield/persistence are found to be ideal for hedgerow planting in the understorey of homesteads. Agathi is not amenable to heavy pruning, hence frequent replanting is a management option due to its faster growth. Cultivation of Moringa should be confined to light intensive as well as dry areas of homesteads. Moreover, pruning of overhead trees in homesteads to enhance understorey light regimes can further elevate the yield levels of fodder banks. Scientific cultivation and management of multispecies tree fodder banks and feeding mixed forages will provide quality and balanced nutrition to enhance livestock production at minimal cost in homegardens.ThesisItem Open Access Comparative performance of mulberry (Morus indica L.) and subabul (Leucaena leucocephala Lam.) under diverse management regimes in a coconut based fodder production system(Department of Silviculture and Agroforestry, College of Forestry, Vellanikkara, 2016) Reshma, M Raj; KAU; Asha, K RajThe research project entitled “Comparative performance of mulberry (Morus indica L.) and subabul (Leucaena leucocephala Lam.) under diverse management regimes in a coconut based fodder production system” was carried out at Instructional Farm, College of Horticulture, Vellanikkara during 2015-2016. The main objective of the study was to assess the influence of plant density and pruning frequency on forage yield and nutritional qualities of mulberry and subabul intercropped in coconut gardens; and to explore the soil fertility changes associated with these intercropping systems. The treatments consisted of two fodder tree species; mulberry and subabul, under three levels of plant density (49,382 plants ha-1, 37,037 plants ha-1 and 27,777 plants ha-1) and three levels of pruning frequency (8, 12 and 16 weeks interval) in all possible combinations with split plot design replicated thrice. The results revealed that both subabul and mulberry produced comparable dry fodder yields under coconut plantation. However, significant variation was noted with regard to proximate composition. The CP content in fodder biomass was significantly higher and CF % lower in subabul than mulberry. However, mulberry had higher ash (6.70 %) and P content (0.58 %) than subabul. Leaf- stem ratio was found to be comparable in both the tree species. Comparing plant densities, highest density yielded more dry matter (12.48 Mg ha-1yr-1) than the lowest one (7.32 Mg ha-1yr-1), with higher leaf-stem ratio (1.34). Total N, CP and P content increased and CF % decreased at higher densities indicating closer spacing for production of tender nutritive fodder. Pruning interval had no significant influence on fresh fodder yield, whereas dry yield was higher for 12 and 16 week intervals. However, leaf -stem ratio was higher at 8 week interval, indicating more foliage production than stem fraction when harvested at shorter intervals. Pruning frequencies had profound influence on nutritive value of the forage. Harvesting at shortest interval of 8 weeks yielded fodder with maximum CP (18.51 %), and phosphorus content (1.1 %), and least CF content (41.91 %) compared to 12 and 16 weeks. Ash content (8.70 %) in fodder was significantly higher at the longest interval of 16 weeks. Comparing interaction effects, for both mulberry and subabul, planting at the highest density (49,382 plants ha-1) and pruning at shortest interval (8 weeks) yielded the maximum fodder (11.05 & 12.17 Mg ha-1yr-1 dry yields for mulberry and subabul respectively) with superior quality (T1 & T10). B:C ratio was also found to be higher in the above systems.Intercropping subabul and mulberry in coconut garden under different management practices produced significant changes in some soil parameters after the initial year of establishment. In comparison to the sole coconut plot, soil properties like OC, pH, EC, WHC and available N, P, K content significantly improved in the high yielding treatment combinations of T1 and T10. Comparing T1 and T10, all soil parameters excelled in T1 except available N content, which was higher in T10.Hence, in conclusion, forage yield and nutritive value of mulberry and subabul underneath coconut garden could be optimized at the cheapest levels by adopting a tree density of 49,382 plants ha-1 and pruning interval of 8 weeks. In comparison, subabul yielded more dry matter and CP, whereas mulberry was superior in ash and mineral content. Establishment and proper management of these tree fodders in coconut garden and feeding mixed fodders thus offers a cheap source of quality forage to Kerala farmers against the highly expensive concentrate feeds.ThesisItem Open Access Performance of calliandra (Calliandra calothyrsus meissn.) under diverse mangement regimes in a coconut based hedge row fodder production system(Department of Silviculture and Agroforestry, College of Forestry, Vellanikkara, 2017) Anu Sagaran, K; KAU; Asha, K RajA study entitled “Performance of calliandra (Calliandra calothyrsus Meissn.) under diverse management regimes in a coconut based hedge row fodder production system” was carried out at Instructional Farm, College of Horticulture, Vellanikkara during 2014-2015. The main objective of the study was to assess the influence of management practices like tree density, pruning height and pruning frequency on initial growth, forage yield and nutritional qualities of calliandra intercropped in coconut gardens under humid tropical conditions of Kerala. The treatments consisted of three levels of plant density (27,777; 22,222 and 17,777 plants ha-1), three levels of pruning frequency (8, 12 and 16 weeks interval) and two levels of pruning height (0.5m and 1m) in all possible combinations laid out under factorial randomized block design with three replications. The results revealed that various management practices had a profound influence on the forage yield and quality aspects of calliandra when grown as an intercrop in coconut garden. Comparing plant densities, highest density stand (27,777 plants ha-1) yielded 55 percent more forage (11.73Mg ha-1yr-1, dry basis) than the lowest density (17,777 plants ha-1), with higher foliage fraction. Quality parameters of forage like crude protein, ash, dry matter, phosphorus and potassium content increased and crude fibre content decreased at higher densities indicating closer spacing for production of tender nutritive fodder. Pruning at the prolonged interval of 16 weeks yielded more total forage, but the majority of the fodder comprised of stem fraction as indicated by the poor leaf-stem ratio. Leaf –stem ratio of fodder harvested at 8 and 12 weeks showed an increment of 125 percent over that of the 16 weeks interval, indicating more foliage production than stem fractions when harvested at shorter intervals. Pruning frequencies also had profound influence on nutritive value of the forage. Harvesting at shortest interval of 8 weeks and 12 weeks yielded fodder with maximum crude protein, phosphorus and potassium content when compared to 16 weeks. Ash and dry matter content in 99 fodder was significantly higher at the longest interval of 16 weeks. Crude fibre content of forage increased sharply from 28.33 to 49.98 percent by prolonging the harvest interval from 8 to 16 weeks thereby adversely affecting the palatability of the forage. Pruning height showed more prominent influence on forage yield of calliandra than the nutritive parameters. Dry fodder yield increased from 8.11 to 10.81 Mg ha-1yr-1 with increasing pruning height from 0.5 to 1m, with a higher leaf-stem ratio for taller stocks. Similarly there was a significant improvement in CP yield from taller stocks (1.67 Mgha-1 )when compared to shorter ones (1.23 Mgha-1) The interaction effects of plant density, pruning height and pruning frequency had no significant effect on yield and quality parameters of callianrda. The highest yielding combination (13.39 Mg ha-1dry basis) was found to be D1H2F2 (27,777 plants ha-1 + pruning height 1 m + pruning interval 12 weeks ) with higher foliage fraction and better nutritive parameters, compared to all other management levels, which were inferior either in forage yield or nutritive value or palatability of forage. On the whole, the study revealed that forage yield and quality of young stands of calliandra underneath coconut garden could be optimized at the cheapest level by adopting a tree density of 27,777plants ha-1, pruning height of 1m and pruning interval of 12 weeks. Moreover, based on the growth and yield performance and quality aspects, it is found that calliandra is a promising fodder tree, which can be successfully integrated with the existing coconut gardens of Kerala. Establishment and proper management of calliandra in coconut garden at appropriate management levels thus offers a cheap source of quality forage to Kerala farmers against the highly expensive concentrate feeds.ThesisItem Open Access Forage yield, soil fertility and carbon dynamics of calliandra (Calliandra calothyrsus meissn,) in coconut plantation(Departament of Silviculture and Agroforestry , College of Forestry, Vellanikkara, 2017) Jilna Joy; KAU; Asha, K RajA study entitled “Performance of calliandra (Calliandra calothyrsus Meissn.) under diverse management regimes in a coconut based hedge row fodder production system” was carried out at Instructional Farm, College of Horticulture, Vellanikkara during 2014-2015. The main objective of the study was to assess the influence of management practices like tree density, pruning height and pruning frequency on initial growth, forage yield and nutritional qualities of calliandra intercropped in coconut gardens under humid tropical conditions of Kerala. The treatments consisted of three levels of plant density (27,777; 22,222 and 17,777 plants ha-1), three levels of pruning frequency (8, 12 and 16 weeks interval) and two levels of pruning height (0.5m and 1m) in all possible combinations laid out under factorial randomized block design with three replications. The results revealed that various management practices had a profound influence on the forage yield and quality aspects of calliandra when grown as an intercrop in coconut garden. Comparing plant densities, highest density stand (27,777 plants ha-1) yielded 55 percent more forage (11.73Mg ha-1yr-1, dry basis) than the lowest density (17,777 plants ha-1), with higher foliage fraction. Quality parameters of forage like crude protein, ash, dry matter, phosphorus and potassium content increased and crude fibre content decreased at higher densities indicating closer spacing for production of tender nutritive fodder. Pruning at the prolonged interval of 16 weeks yielded more total forage, but the majority of the fodder comprised of stem fraction as indicated by the poor leaf-stem ratio. Leaf –stem ratio of fodder harvested at 8 and 12 weeks showed an increment of 125 percent over that of the 16 weeks interval, indicating more foliage production than stem fractions when harvested at shorter intervals. Pruning frequencies also had profound influence on nutritive value of the forage. Harvesting at shortest interval of 8 weeks and 12 weeks yielded fodder with maximum crude protein, phosphorus and potassium content when compared to 16 weeks. Ash and dry matter content in 99 fodder was significantly higher at the longest interval of 16 weeks. Crude fibre content of forage increased sharply from 28.33 to 49.98 percent by prolonging the harvest interval from 8 to 16 weeks thereby adversely affecting the palatability of the forage. Pruning height showed more prominent influence on forage yield of calliandra than the nutritive parameters. Dry fodder yield increased from 8.11 to 10.81 Mg ha-1yr-1 with increasing pruning height from 0.5 to 1m, with a higher leaf-stem ratio for taller stocks. Similarly there was a significant improvement in CP yield from taller stocks (1.67 Mgha-1 )when compared to shorter ones (1.23 Mgha-1) The interaction effects of plant density, pruning height and pruning frequency had no significant effect on yield and quality parameters of callianrda. The highest yielding combination (13.39 Mg ha-1dry basis) was found to be D1H2F2 (27,777 plants ha-1 + pruning height 1 m + pruning interval 12 weeks ) with higher foliage fraction and better nutritive parameters, compared to all other management levels, which were inferior either in forage yield or nutritive value or palatability of forage. On the whole, the study revealed that forage yield and quality of young stands of calliandra underneath coconut garden could be optimized at the cheapest level by adopting a tree density of 27,777plants ha-1, pruning height of 1m and pruning interval of 12 weeks. Moreover, based on the growth and yield performance and quality aspects, it is found that calliandra is a promising fodder tree, which can be successfully integrated with the existing coconut gardens of Kerala. Establishment and proper management of calliandra in coconut garden at appropriate management levels thus offers a cheap source of quality forage to Kerala farmers against the highly expensive concentrate feeds.ThesisItem Open Access Autoallelopathy of selected multipurpose tree species and the effect of their leachates on Agricultural test crop(Department of Silviculture and Agroforestry, College of Forestry, Vellanikkara, 2017) Neenu, P; KAU; Jamaludheen, VA study carried out in the tree nursery of College of Forestry, Vellanikkara, Thrissur to assess the autoallelopathic effect of selected multipurpose trees and the effect of their leachate on agricultural test crop. The study on allelopathy is very essential in agroforestry as it effect the yield and performance of the trees and crops grown together and is essential to make judgment on the compatibility of trees and crops. The allelopathic effect of different tree part leachates such as leaf leachate, bark leachate and root leachate of selected trees viz., Acacia auriculiformis, Acacia mangium, Ailanthus. triphysa, Grevillea robusta and Swietenia macrophylla on the germination and growth of their own seedling and an agricultural test crop cowpea (Var. Anaswara) were studied. The soil for the pot culture experiment was collected from well established plantations of the MPTs and is used as potting mixture with sand in equal proportion. The pots were irrigated with leachates of different tree parts of these trees by soaking the tree part in water for 24 hours in 1:10 w/v concentration. The monthly variation in nutrient status of the soil used for pot culture experiment and the variation in the physicochemical properties of leachates at six intervals is also estimated. The effect of tree part leachates considerably varied among the germination and biomass production in both allelopathic and autoallelopathic studies. The observations on the germination per cent in allelopathic and autoallelopathic study revealed greater inhibition in the pots treated with leaf leachate in all tree species, except for S. macrophylla. With regard to biometric observations and biomass production also, S. macrophylla performed as the best compared to other selected species investigated for autoallelopathy. In case of the test crop also, it showed a better growth in pots treated with the leachates from S. macrophylla. The physicochemical analysis of the leachate of tree parts used to irrigate the pots showed increasing trend in total solid, electrical conductivity, total phenol, total carbohydrate and a decreasing trend in pH upto 36 hours. The physicochemical analysis of leachates for total phenol showed a greater concentration in the leaves than the bark and root. Results converge to the generalisation that among the five selected tree species the effect of auto allelopathy is negligible in case of S. macrophylla. The better growth performance of the test crop in S. macrophylla tree part leachates shows the compatibility of the test crop with the tree than the other selected tree species.
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