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ThesisItem Open Access Standardisation of planting stock production techniques for teak (Tectona grandis Linn.f.)(Department of Silviculture and Agroforestry, College of Forestry, Vellanikkara, 2020) Vijayalakshmi, K P; KAU; Jamaludheen, VThe study was undertaken at Tree Nursery of College of Forestry to compare the effect of different pre-treatment methods on seed germination and optimization of fertigation intervals and seed sowing at different spacing for quality teak stump production. Attempt was also made to select ideal potting media and to standardize container type and size for producing quality teak seedlings. The treatment combination of termite scarified seeds + Alternate wetting and drying (AWD)-3 days gave the highest germination percentage (92.33 %). This resulted in 18.56 % increase in germination percent against the 73.77 % in the AWD 7 days alone (Standard Pre-treatment followed). The dual advantages of the treatment combination of termite scarified seeds + AWD-3 days with respect to both high a germination percentage and the lesser number of days required for the pre- treatment of teak seeds is an important highlight. Termite scarified seeds gave the highest collar diameter of 1.46 mm as against the control treatment (0.81 mm) after 30 days of germination. The superiority of this treatment was evident, in most of the seedling growth characters in the nursery also, as in shoot length (6.43 cm), root length (13.04 cm), total seedling length (19.48 cm), dry weight (0.20 g) and vigour index (14.91). Mechanical scarification also has shown advantage over the untreated seeds as it followed as the next best treatment in germination percentage and in most of the early seedling growth characteristics. Hence, in situations where the suitable subterranean termite cannot be assured, mechanical scarification using the mechanical scarifier is recommended. For quality teak stump production, at 180 days, the maximum collar diameter (23.31mm) showed by Fertigation at 7 days interval was significantly superior to all other treatments. Moreover, at 180 days, all the fertigation treatments reached the minimal collar diameter criteria of 1-2 cm were statistically distinct from the no fertigation (control) treatment. All the fertigated treatments attained collar diameter of 2-3 cm criteria for better teak stump production. It is also proved that even the least frequent fertigation at 21 days application resulted in the collar diameter of (22.66 mm) at 180 days of growth period. Hence, fertigation with 0.2 % N: P: K (19:19:19) in equal proportion at 21 days interval can be recommended for producing seedlings for better stump production. Seed sowing at 10 cm x 10 cm also reached required collar diameter for stump production. That means, 1000 numbers of utilisable seedlings are available for stump production from a standard nursery bed of 10 m x 1m at 180 days of seedling growth. At 180 days, the treatment interaction F1 X S3 (Fertigation at 14 days interval X Spacing at 30cm X 30cm) showed the maximum collar diameter (34.88 mm) followed by F2 X S3 and F3 X S3 (32.00 and 31.75 mm), these two were on par with each other. Taking into account the number, the treatment combination S1 X F3 (10 cm X 10 cm with 21 days intervals of fertigation) is recommended as it produces 1000 numbers of seedlings fit for better stump production from a standard nursery bed size of 10 m X 1m. The treatment S1 X F4 (10 cm X 10 cm) with no fertigation also reached the minimal collar diameter (11.51 mm) criteria of 1-2 cm. Good correlation existed between root growth potentials and most of the seedling characteristics needed for good quality teak stump with six months of seedling growth. Among the potting media the maximum seedling length (138.00 cm), collar diameter (8.77 mm), total dry weight (17.77 g) and the highest quality index (0.98) recorded in M3-Soil+ Rice husk+ Vermicompost in the ratio of 2:1:1 as against the standard potting media M5 (Soil+ Sand+ FYM) normally used for raising seedlings. Apart from the observed improvement in plant growth, the production cost of planting stock was found comparable for M3 (soil+ rice husk+ vermicompost) 2:1:1 mixture (₹ 9.09 / plant) as against the cost for standard potting mixture (₹ 9.01 / plant) and the treatment M4-Coir pith+ vermiculite+ perlite was found as the costliest (₹ 13.02 / plant). Both from the seedling quality and from the economic point of view, the treatment M3- Soil+ rice husk+ vermicompost was emerged as the best. Among the polythene bags, 30 cm x 25cm (T1) raised seedling exhibited maximum number of leaves (15.25), leaf area (4025.95 cm2), shoot length (106.89 cm), collar diameter (13.50 mm), the number of primary lateral roots (58.12), length of primary lateral roots (38.96 cm) maximum root length (48.74 cm), total dry weight (60.37 g) and quality index (4.56) at 90 days after transplanting. Among the different root trainers, 300 cc raised seedlings showed maximum number of leaves (11.12), leaf area (435.08 cm2), collar diameter (6.91 mm), shoot length (27.09 cm), root length (23.80 cm), total seedling length (50.90 cm), number of primary lateral roots (51.25), length of primary lateral roots (19.80 cm), leaves dry weight (2.11 g), shoot dry weight (3.46 g), total dry weight (6.61 g) and quality index (0.84) as against the T6-Root trainer of 150 cc (Standard size/control). The production cost of planting stock was found (₹ 9.09 and ₹ 7.89 / plant) for T4-Root trainer of 300 cc and T5-Root trainer of 200 cc and T6-Root trainer of 150 cc - Standard size/control (₹ 6.99 / plant). From the results of the study, it is advisable to adopt root trainer of 300 cc only if the additional cost of ₹ 2.10 can be spent per seedling, otherwise go for the standard size of 150 cc for there was no distinct advantage of adopting the next bigger size of 200 cc. The prominent managerial inputs form this study for teak nursery production forestry include development of standard protocols for pre-treatment, seed sowing spacing, potting media, size of the polythene bags and root trainers. The package for quality teak stump production was also standardised.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 Selection and evaluation of superior planting materials of Ailanthus triphysa (Dennst.) in Thrissur(Department of Silviculture and Agroforestry, College of Forestry, Vellanikkara, 2018) Abijith, R; Jamaludheen, VA nursery and field experiment was conducted to evaluate the superior performance of selected candidate plus trees of Ailanthus triphysafrom the Thrissur District, Kerala. The demand of this timber was very much increased because of its fast growing nature and diversity of utilizations. Hence, the tree improvement of this species is the need of the hour that might result increased quality and reduced rotation time. The possible gain expected through the phenotypic selection can also be directly utilised by the tree growers. The candidate plus trees were identified and selected by adopting the comparison tree method. The seeds collected were used to study the germination parameters at tree nursery of College of Forestry, Kerala Agricultural University. The initial growth performances of the progenies of the selected CPTs were evaluated at nursery in a completely randomised design and also at the field in a randomised block design and the data were statistically analysed using Analysis of Variance technique. The progenies of the selected CPTs showed significant variation in their initial growth parameters. The highest germination per cent of 83.50 was exhibited by CPT-11 and the lowest of 67 per cent by CPT-1. After the six months of observation in the nursery, CPT-11 attained the maximum height of 88.67cm and lowest height by CPT-5 (76.33cm). The maximum plant height (99 cm) and girth (21.04 cm)in the field was also exhibited by CPT-11. The CPT-11, CPT-10 and CPT-9 were the top performers compared to other selections. The CPT-1 was the inferior in the nursery and also in the field. The CPTs that exhibited superiority in germination percentage, germination value and mean daily germination also exhibited distinctively superior growth in the nursery and in the field. In fact, the identification and selection of superior quality planting materials of Ailanthus triphysahas a greater role in the tree improvement. The single tree selection is the best method for the production of superior progenies and this can be useful for the future afforestation and seedling production for getting high quality timber with short rotation period. From this study we recommend CPT-11, CPT-10 and CPT-9 for achieving these objectives.ThesisItem Open Access Optimization of fertilizer regimes and understorey productivity in four-year-old Swietenia macrophylla King stands(Department of Silviculture and Agroforestry, College of Forestry, Vellanikkara, 2018) Vikas Kumar; KAU; Kunhamu, T KExtensive field study was carried out to investigate the effect of fertilizer treatment and intercrops on the growth and productivity of 4-year-old Swietenia macrophylla King. The study was carried out in a S. macrophylla plantation that was established at Mala, Thrissur during 2009 at a spacing of 2.5 x 2.5m. The fertilizer cum intercropping trial was superimposed on the existing S. macrophylla plantation in a split plot design with fertilizer levels as main plots and intercrops as sub plots during two consecutive years (2014-2016). The various N, P, K fertilizer combinations were viz. F1: 0:0:0; F2-50:25:25 (68:78:26 g per tree); F3- 100:50:50 (136:156:52 g per tree) and F4-150:75:75 (205:234:78 g per tree) kg ha-1 year-1 N, P2O5 and K2O; equivalent to 0:0:0, 50:10.75:20.75, 100:21.5:41.5 and 150:32.25:62.25 kg ha-1 per year elemental N, P and K, respectively. The fertilizers were applied to the mahagony trees at a basal ring of 50 cm radius just after the pre-monsoon rains. The various intercrops selected were shade tolerant ginger (Zingiber officinale Roscoe), wild turmeric (Curcuma aromatic Salisb) and turmeric (Curcuma longa L.). There were total 16 combinations of treatments with three replications (total 48 plots). The main plot size was 40 x 10 m and sub plot 10 x 10 m. The growth observation of the S. macrophylla tree after the fertilizer application showed consistent increase with increasing fertilizer dosage. Tree growth in terms of height, diameter, basal area and volume showed characteristic increase with increase in fertilizer levels. For instance, the stand basal area increased from 8.69 (F1: unfertilized) to 14.87 m2 ha-1 (F4: heavily fertilized). Similarly the tree volume also showed increase with fertilizer application. The difference in basal area for the higher fertilizer regimes were on par (F3, 14.50 m2 ha-1 and F4, 14.87 m2 ha-1) suggesting F3 as the optimal fertilizer regime if basal area production is the objective. However, the volume production was the highest under F4 regimes (105.28 m3 ha-1) which was significantly different from F3 (93.31 m3 ha-1). Hence tree management at F4 fertilizer regime would be ideal for optimal volume production for S. macrophylla. The biomass production results also showed positive response to applied fertilizers. Total mean tree biomass production was in the order 52.24, 60.62, 64.32 and 83.62 kg per tree for F1, F2, F3 and F4 fertilizer dosage regime respectively. The corresponding stand level biomass (per ha basis) was in the order 83.59, 97.00, 102.91 and 133.80 Mg ha-1 for F1, F2, F3 and F4 fertilizer dosage regime respectively. The highest fertilizer dosage plots showed almost 60 per cent increase in biomass production as compared to unfertilized control. Among the biomass components, stemwood represented almost 50 % of the total biomass production for all fertilizer regimes followed by roots which accounted almost 18 % of total biomass production. Branchwood biomass represented roughly 14-15 % of total biomass. Biomass accrual by the various components in the decreasing order was: stemwood> roots> branch wood >leaves>twigs. Mean tree and stand level carbon sequestration showed positive response to fertilizer application for 6 year old S. macrophylla. The total mean tree carbon stocks ranged from 29.1 kg (F1) to 46.66 (F4). The total carbon sequestration on per hectare basis was 74.66, 57.24, 54.31, and 46.56 Mg ha-1 for fertilizer regimes F4, F3, F2 and F1 respectively.Among the various biomass components, stemwood accounted bulk of the biomass carbon which was roughly 50% followed by roots (17 %). Nutrient partitioning S. macrophylla suggests that in general, nitrogen and potassium concentrations decreased in the order leaves > stem > branch > roots > twigs for N, P and K. However, tissue phosphorus concentration followed the order branches > leaves > roots > twigs > stem. Various components stored considerable amount of nutrients in their biomass. The total N stock in the standing biomass ranged from 0.428 (unfertilized control) to 0.716 Mg ha-1 (F4; heavily fertilized). The stock of phosphorus in the biomass was 0.174 (unfertilized control) to 0.223 Mg ha-1 (F4; heavily fertilized) while the corresponding stock for potassium was 0.090 (unfertilized control) to 0.144 Mg ha-1 (F4; heavily fertilized). Root distribution studies using logarithmic spiral trench technique in 6-year-old S. macrophylla showed increase in rooting intensity with fertilizer application for total roots and root class <2.5 mm. Fine root (< 2.5 mm) represented approximately 58 to 62 % of the total roots. Hence the increase in fine root count in high fertilized plots suggest higher nutrient uptake and there by higher tree growth for S. macrophylla. The present study showed the maximum foraging zone for S. macrophylla was at rhizosphere volume of 2.17 m lateral distance and 40 cm soil depth. At the present stocking this leads to considerable overlapping of the rhizosphere of S. macrophylla and intercrops and thereby limits the prospects of intercropping. Hence the possible optimal spacing suggested for 6-year-old S. macrophylla would be 5.5 m x 5.5 m for effective intercropping. Effect of intercrop on the tree growth in all the fertilizer treatment plots suggested non-significant response. Despite the overwhelming effect of fertilizer on tree growth and yield, the presence of intercrop had only very modest influence on tree growth. Interestingly some of the S. macrophylla tree growth variables were marginally better in the intercropped plots suggesting possible complementary interaction between the intercrop and trees for applied fertilizers. The intercrops viz. ginger, wild turmeric and turmeric showed better growth in fertilized plots as compared to unfertilized control. Also the biometric growth and rhizome yieldswere higher in the treeless open control plots as compared to S. macrophylla intercropped plots. Nevertheless the growth differences were lower in the heavily fertilized plotsas compared to open control. The better growth and rhizome yields during the second year for all the three intercrops was due to improvement in understory light regimes consequent to uniform tree pruning.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.
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