Source Of Seeds Research Articles

Invasion of Siberian Elm (Ulmus pumila) Along the South Platte River: the Roles of Seed Source, Human Influence, and River Geomorphology

Invasion of Siberian Elm (Ulmus pumila) Along the South Platte River: the Roles of Seed Source, Human Influence, and River Geomorphology

Influence of Seed Source and Soil Contamination on Ecophysiological Responses of Lavandula pedunculata in Rehabilitation of Mining Areas.

Mining activities have turned many areas of the Iberian Pyrite Belt (IPB) into extreme environments with high concentrations of metal(loid)s. These harsh conditions can inhibit or reduce the colonization and/or development of most vegetation. However, some species or populations have developed ecophysiological responses to tolerate stress factors and contaminated soils. The main objectives of this study are: (i) to assess the differences in germination, growth, development and physiological behaviour against oxidative stress caused by metal(loid)s in Lavandula pedunculata (Mill.) Cav. from two different origins (a contaminated area in São Domingos mine, SE of Portugal and an uncontaminated area from Serra do Caldeirão, S of Portugal) under controlled conditions; and (ii) to assess whether it is possible to use this species for the rehabilitation of mine areas of the IPB. After germination, seedlings from São Domingos (LC) and Caldeirão (L) were planted in pots with a contaminated soil developed on gossan (CS) and in pots with an uncontaminated soil (US) under controlled conditions. Multielemental concentrations were determined in soils (total and available fractions) and plants (shoots and roots). Germination rate, shoot height, dry biomass and leaf area were determined, and pigments, glutathione, ascorbate and H2O2 contents were measured in plant shoots. Total concentrations of As, Cr, Cu, Pb and Sb in CS, and As in US exceed the intervention and maximum limits for ecosystem protection and human health. The main results showed that L. pedunculata, regardless of the seed origin, activated defence mechanisms against oxidative stress caused by high concentrations of metal(loid)s. Plants grown from seeds of both origins increased the production of AsA to preserve its reduction levels and kept the contents of GSH stable to maintain the cell’s redox state. Plants grown from seeds collected in non-contaminated areas showed a high capacity for adaptation to extreme conditions. This species showed a greater growth capacity when seeds from a contaminated area were sown in uncontaminated soils. Thus, L. pedunculata, mainly grown from seeds from contaminated areas, may be used in phytostabilization programmes in areas with soils with high contents of metal(loid)s.

Effect of Root Pruning on the Root Growth Potential (RGP) of Three Philippine Native Tree Species

Root growth potential (RGP) is the plant’s capacity to grow new roots, an important trait for seedlings to be used on any reforestation program. In the Philippines, these kinds of programs often end up in failure, as low-quality seedlings are usually chosen due to unfamiliarity with attributes that indicate good outplanting performance, narrow sources of high-quality seeds, and the lack of a reliable quality assessment method. This study aimed to determine the RGP of three native species – namely, bignai (Antidesma bunius), kamagong (Diospyros blancoi), and molave (Vitex parviflora) – and find its correlation with other morphological parameters. The experiment was done in a completely randomized design (CRD) with taproot pruning lengths (1-cm pruning, 2-cm pruning, and no root pruning) applied as treatments for each species. The morphological parameters measured included the relative growth rate (height and diameter), number of leaves, root collar diameter (RCD), biomass (root, shoot, and total) and length of taproot while root-shoot ratio, sturdiness quotient, and seedling quality index (SQI) were calculated. In general, taproot pruning had no significant effects on the seedling morphological attributes of all species. Excluding molave, the two other species had mostly responded well to root pruning and can be recommended as a treatment to induce root growth development. RGP had generally complemented the results from the other parameters, indicating how root development was associated with the morphological growth of the species. The study shows how RGP can also be relied on for testing seedling health and the status of native species. For a more comprehensive result, future research could increase experiment duration or use younger seedlings. A field performance assessment could also be performed to supplement the RGP study

The role of institutions in enhancing farmer motivation to carryout corn seed production under corporation system

A farmercorporation-based seed production system is needed to bring seeds closer to farmers. Its developmen requires support from several institutions related to the policy of providing seeds for farmers. This study aims to determine the role of the institution in the farmer-based hybrid maize production system. Five institutions evaluated for their role, namely Indonesian Cereals Research Institute (ICERI) as a source of seeds and technology, Assessment for Agricultural Technology (AIAT) as aassistence for application technology in the field, Agricultural Service Office as a policymaker in available seed for farmer, Seed Certification and Inspection Center (SSO) as the supervisor of seed quality, and the grower local as an absorber of the results by farmer groups. The role of the institution is observed through: socialization activity, field observations, and discussions. The results showed that all institutions have gave various supports. ICERI has provided seeds in a timelymanner, the right quality and the right quantity, and also conducts regular training and monitoring to provide instructions for implementing good technology application to farmers and by farmers it is considered very good. AIAT provides field assistance for the application of production technology, but the activities are considered by farmers to be inadequate, the staff of Agriculture Service continue to motivate farmers and farmers are deemed adequate. SCIC as a seed supervisor continues to assist farmers in the field, in addition to monitoring irregularities, it also continues to provide guidance to farmers in accordance withthe standar operational procedure of hybrid maize seeds and is considered very good by farmers. Then the seed producers who absorb the results of the farmers have carried out excellent guidance such as placing quality control personnel in the field to control implementation, absorbing farmers’ products at an agreed price, building a processing unit in the site area, and by the farmers it is considered very good. With adequate support from related institutions, farmers continue to be motivated to produce hybrid maize seeds, which were originally only 100 ha in Minahasa district, then expanded to surrounding districts, sothat the area production increase from 253,4 ha in 2019 to 480 ha in 2020.

Yield and yield component performance of soybean promising line in upland during the rainy season

Soybean development in dry land during the rainy season not only contributes to soybean production but also has the potential to be a source of seeds. The research aimed to identify the yield and yield component performance of soybean promising line at upland in the rainy season. A total of fourteen soybean promising lines and two check cultivars were evaluated for their yield and yield components in Blitar and Malang. The field experiments were conducted in each location during the rainy season 2021 using a randomized block design with four replicates. A significant GEI was found on the plant height, number of branches/plant, number of nodes/plant, number of filled pods/plant, and 100 seed weight. The Blitar location indicated resulting in the optimum yield and yield components of the tested promising lines. The average yield in Blitar was 2.81 t/ha (an average of 2.07 – 3.60 t/ha) and in Malang was 2.16 t/ha (an average of 1.52 – 3.18 t/ha). The number of branches and number of nodes has significant roles in determining the seed yield in soybean. Two genotypes with consistently high yield in Blitar and Malang are recommended to be evaluated in further advanced yield trials in different environments.

Effect of sucker weight and seedling site on the growth of sago seedlings (Metroxylon sago Rottb.) in Papua

This study aims to obtain sucker weight and appropriate seedling site as a source of sago seeds by using seedling techniques in polybags to improve seed quality on sago cultivation. The experiment used a factorial design arranged in a randomized block design with three replications. Factor A, namely sucker weight, consisted of <999 g, 1000-1499 g, 1500-1999 g and > 2000 g. Factor B is the seedling site, consisting of laying seeds in the field, greenhouse and paranet of 60%. The results of the study showed that there was no interaction between the sucker weight combined with the seedling site, but the sucker weight had a significant effect on the number of rachis and the number of primary roots per plant and the percentage of life seedlings. Higher rachis growth was 3.8 obtained from medium-sized sucker weights (1000-1499 g and 1500-1999 g) and the highest number of primary roots was 41.3. It is obtained at sucker weights of 1000-1499 g. Meanwhile, the higher percentage of seedling survival was obtained at medium to large sucker weights of 66.3-71.0%. Thus, multiplication of sago seeds using medium-sized sucker on polybag media is highly suggested.

Pengaruh Metode Budidaya dan Asal Bibit terhadap Pertumbuhan Gracilaria verrucosa Yang Dibudidayakan Di Tambak Desa Kaliwungu, Kabupaten Brebes

Gracilaria verrucosa is one of the seaweeds with good economic value that can be cultivated in ponds. The demand for Gracilaria is increasing as an ingredient for food, beverage, cosmetic, pharmaceutical manufacturing industries. The factors that determine the success of Gracilaria culture: cultivation methods include the seeds quality and source.This study aims to determine the effect of different Gracilaria seeds sources and its culture methods on its growth, to determine the interaction between methods and seed sources. This study aims to determine the effect of different Gracilaria seeds sources and its culture methods on its growth, to determine the interaction between methods and seed sources The research was conducted in October-November 2020 in Kaliwlingi Village, Brebes District, Brebes Regency, Central Java. The experimental used was factorial design with 2 factors: Factor 1: seed sources (A): A1 = Seed from Semarang; A2 = seed from Brebes; A3 seeds from Demak. Factor 2: cultivation method (B): B1 = longline; B2 = off-bottom; B3: broadcast. So there were 9 treatment combinations: A1B1, A2B1, A3B1; A2B1, A2B2, A2B3; A3B1, A3B2, A3B3, each treatment with 3 replications. The data collected include: growth of gracilaria during 60 days. The Specific Growth Rate (SGR) analyzes using ANOVA. The results showed the origin of seedlings and cultivation methods have a very real effect (P&lt;0.05) on SGR Gracilaria. The highest SGR was at treatment A1B1 (Semarang seeds longline method) = 1.84±0.17%/day, and the lowest was treatment A3B3 (Demak seedlings broadcast method) of 0.25±0.13%/day. The water quality measurement results obtained indicate that the water quality at the research location is in a tolerable range for the growth of seaweed. Keywords: Gracilaria, seed source, longline, broadcast, off-bottom.

Chemical Properties of 15-year-old Teak (Tectona grandis L.f) from Different Seed Sources

Fifteen year-old teak wood samples planted in Ciamis FMU (Perhutani Enterprise) were evaluated for their chemical properties. Three seed sources such as conventional seed, clone, and superior wood and radial positions namely sapwood, outer heartwood, and inner heartwood were the observed factors. The specimens were taken from the bottom parts of their sources. Completely randomized design was used. Cell wall components were analyzed by various gravimetric methods.Analysis of variance and Duncan’s test were performed for data analysis. The results showed that no significant difference in the quantity of cell wall components (cellulose, hemicellulose, and lignin), extractives (ethanol-toluene and hot-water solubles), ash, and silica content among the seed sources. Superior teakwood or Jati Plus Perhutani, which has the highest growth rate (2.1~3.6 cm/year) among others, showed a comparative higher average pH values (7.08~7.38) and solubility in 1% NaOH (17.22~17.83%) than other sources. Radial factors significantly affected ethanol-toluene extractive and lignin content. The ethanol-toluene extractive had the highest content (9.30~11.54%) at the outer part of heartwood while lignin content was the lowest (28.12~30.10%) in the inner part. The result indicated some good characteristics of young teak trees compared to the mature ones in relation to wood processing.

DOES CLEISTOGAMOUS SELF-FERTILIZATION PROVIDE REPRODUCTIVE ASSURANCE AGAINST SEED PREDATION IN RUELLIA HUMILIS?

Mixed mating is thought to be adaptive in many species of flowering plants because self-fertilization provides reproductive assurance when pollinator densities are low. In species with dimorphic flowers, automatic self-fertilization by small cleistogamous (CL) flowers might also provide reproductive assurance by avoiding floral herbivory. We tested this hypothesis by quantifying flower production, seed production, and seed predation across an entire reproductive season within a Missouri population of Ruellia humilis, a species with mixed mating enforced by dimorphic flowers. The production of CL flowers was delayed relative to the production of open-pollinated chasmogamous (CH) flowers, consistent with the hypothesis of reproductive assurance. The rate of seed predation by larvae of the Noctuid moth Tripudia rectangula was much higher for fruits produced by CH flowers (69%) than by CL flowers (18%). Thus, although CH flowers self-pollinate in the absence of outcross pollen, CL flowers are a much more economical source of selfed seeds, not only because they require fewer resources but also because they experience much lower levels of seed predation. Seed predation by Tripudia is common in many other cleistogamous species of Ruellia native to the southern United States and Mexico and might have played a significant role in the evolution of CL flowers in this large genus.

PENGARUH PEMBERIAN PUPUK KOTORAN KAMBING DAN ATONIK TERHADAP PERTUMBUHAN SETEK DAUN MAHKOTA NENAS (Ananas comusus L. Merr) KUALU PADA MEDIA GAMBUT

The Kualu pineapple propagation technique uses crown bud cuttings which is made as a pineapple plant propagation material for peat media that is added with goat manure and several concentrations of Atonic. The aim is to obtain an effective source of cutting material for the procurement of Kualu pineapple seedlings cultivated on peat soil. This research used a Completely Randomized Design (CRD) factorial with two factors. First factor was the dose of goat manure at levels 0, 10, 20, and 30 g/polybag dan second factor was various atonic concentrations at levels 0, 2, 4, and 6 ml/L. The data were statistically analyzed and further tested for honest real difference (BNJ) at the 5% level. The results obtained from the interaction of the two treatment factors were significantly different to the time of shoot emergence and the percentage of shoot life. There was no significant difference in seedling height and number of leaves, as well as the main effect of each treatment. Crown shoot cuttings planted on peat media added 20 g/polybag of goat manure and 4ml/l Atonic obtained a better source of cutting material to be used as a source of seeds than others. The success of obtaining seeds from crown leaf cuttings sources through this research has answered that crown leaf cuttings have potential and great opportunity to be developed.

AFLP analysis of Genetic diversity and Phylogenetic relationships of Vigna radiata (L) Wilczek

Among the important pulse-yielding plants Vigna radiata is important. In the Indian subcontinent, it is an essential source of dietary protein particularly in the vegetarian population. It contains abundant nutrients with biological activities. Soaked seeds are eaten as a good source of protein and mature seeds are cooked or can be sprouted for human consumption. Mung beans and its sprouts contain chemical constituents like flavonoids, phenolic acids, organic acids, amino acids, carbohydrates, and lipids. It is related to different biological activities like antioxidant, antimicrobial, antitumor, anti-inflammatory, anti-diabetic, and antihypertensive effects, etc. The seeds are a traditional source of cures for paralysis, rheumatism, coughs, fevers, and liver ailments. As a green manure or cover crop, the plant can be grown, enriching the soil with the nitrogen formed on its roots. The powerful Amplified Fragment Length Polymorphism (AFLP) is a molecular marker used for a variety of applications like assessing genetic diversity within species or among closely related species, inferring population-level phylogenies, generating genetic maps, and determining the relatedness among cultivars. AFLP has become extremely beneficial in the study of taxa including bacteria, fungi, and plants, where much is still unknown about the genomic makeup of various organisms. A study was made to assess the genetic diversity and phylogenetic relationships of a set of five varieties of Vigna radiata (L) Wilczek using the AFLP technique. Five different varieties of Vigna radiata viz. B1, TARM 2, PDM 84, TM 99, and TM 98 were subjected to AFLP analysis. A total of 471 fragments were scored across all the 12 AFLP primer sets used and the results were used to plot a dendrogram. It was observed that these five varieties formed three distinct groups among which the aromatic B1 variety formed a distinct group.

Community seed network in an era of climate change: dynamics of maize diversity in Yucat\xe1n, Mexico

Local seed systems remain the fundamental source of seeds for many crops in developing countries. Climate resilience for small holder farmers continues to depend largely on locally available seeds of traditional crop varieties. High rainfall events can have as significant an impact on crop production as increased temperatures and drought. This article analyzes the dynamics of maize diversity over 3 years in a farming community of Yucatán state, Mexico, where elevated levels of precipitation forced farmers in 2012 to reduce maize diversity in their plots. We study how farmers maintained their agroecosystem resilience through seed networks, examining the drivers influencing maize diversity and seed provisioning in the year preceding and following the 2012 climatic disturbance (2011–2013). We found that, under these challenging circumstances, farmers focused their efforts on their most reliable landraces, disregarding hybrids. We show that farmers were able to recover and restore the diversity usually cultivated in the community in the year following the critical climate event. The maize dynamic assessed in this study demonstrates the importance of community level conservation of crop diversity. Understanding farmer management strategies of agrobiodiversity, especially during a challenging climatic period, is necessary to promote a more tailored response to climate change in traditional farming systems.

INFLUENCE OF SEED SOURCE ON PLANT GROWTH, YIELD AND YIELD GAP OF RICE (ORYZA SATIVA L.)

Seed source is influenced on plant growth and yield of a crop. The objective of this research was to investigate the plant growth and yield including gap of rice collected seed from different sources in Bangladesh. The seed of rice variety BRRI dhan28 of Oryza sativa L. was used as study material. The treatments were consisted of four sources of seed viz. Bangladesh Agricultural Development Corporation (BADC), private seed company, farmers’ own seed and seed from local market. The seed was also obtained from Bangladesh Rice Research Institute (BRRI) that was used for control. Data regarding plant growth parameters (plant height, leaf area, absolute growth rate, AGR and relative growth rate, RGR); yield attributes (number of spikelet/panicles, 1000-grain weight and yield/ton); and percentage of yield gap were investigated. Minimum plant growth parameters except RGR and all yield attributes of rice were observed in the seed of BRRI followed by BADC; while the highest RGR was observed in the seed of BRRI and BADC simultaneously. The yield gap of rice was the highest in the seed of the market. The plant growth and grain yield of rice were comparatively higher in the seed of BRRI followed by BADC and company due to higher knowledge of seed production and processing technology; while higher yield gap were observed in the seed of farmer and market due to poor seed production and processing facilities as well as their poor knowledge.

Latitude of seed source impacts flowering phenology and fitness in translocated plant populations

Seed sourcing strategies have received considerable attention in the restoration literature and are a key component of effective management for restoration and conservation of natural areas. Research and discussion tend to focus on optimal distances and environmental similarities between seed sources and planting sites. However, given the increasing calls for assisted gene flow and assisted migration, greater consideration of translocating populations in specific directions across climatic gradients is warranted. To the extent that local adaptation proceeds primarily in response to climatic conditions, assisted gene flow across climatic gradients is likely to promote species persistence in the face of climate change. However, if species are adapted to other abiotic and biotic factors, translocating populations across climatic gradients may have unintended and potentially maladaptive consequences. Here, we used extensive collections of seed materials from across the state of Minnesota, a field planting that established common conditions at a location that was near the southern extreme of all the source locations, and subsequent aster modeling of fitness data to examine the overall fitness consequences of translocating populations across the landscape. We found that populations from cooler, northern sources tended to have higher fitness than those from warmer, more southern locations. In addition, populations from more northern locations tended to have earlier flowering phenology relative to populations from more southern sources, perhaps conferring a fitness advantage. Taken together, our results suggest that latitude of origin may be an important factor to take into consideration during seed source selection for restoration work, and that the direction of the effects can be at odds with expectations based on climatic considerations.

Diversity, distribution, agronomic and post-harvest management of local barley (Hordeum vulgare L.) variety in South Wollo, Ethiopia.

The structure of barley varieties were studied, using structured and semi-structured queries, at Legambo, Tenta and Worailu districts of South Wollo, Ethiopia. Eight local barley varieties (Belg, Ginbot, Sene/Nech, Tikur, Holker, Traveler Tegadime and Temezhi) were identified, and got their names found on seed color and planting season. According to farmers, Tegadime is the production leader among all, but the source of seeds and the market chain are the limiting factors for its popularity and this is why it’s not famous is because of the low price of the seed. Thus, Sene/Nech found to be popular and shared 46.91% at Tenta, 48.47% at Legambo and 51.55% at Wereilu followed by Tikur and Ginbote. High barley diversity was noted at Tenta (E = 0.773) followed by Wereilu (E = 0.678) and Legambo (E = 0.606). Sene/Nech (0.67), Belg (0.62), Tegadime (0.59), Tikur (0.55) and Ginbote (0.54) were found to be shared, but Traveler, Holker and Temezhi were rarely found. At farm, most farmers were plowing twice before sowing using horse. Biological fertilizer usages were well practice at Tenta, Legambo and Were’ilu, respectively. While, inorganic fertilizer usage was better at Wereilu, but none at Legambo. Pest management was better at Wereilu and hand weeding is a common system, but low at Legambo, and mowing by sickle, threshing by horse and store in Gotera were a shared practice. Farmers use outdated tools for agricultural practice and the yield is losing due to unavailable of update machinery. So, different managing approaches and new harvesting technologies should address.

Selection of highly productive clove trees in the Anambas population

The productivity of cloves in Indonesia is low, probably due to the use of inferior seeds. The success of plant cultivation is determined by many factors, including the use of quality seeds. This study aims to select high-yielding clove trees, which can be recommended as a quality source of seeds. The research was conducted in Anambas Islands Regency, in a population of cloves belonging to a farmer. A highly productive population was selected as the genetic material following the guidelines for selecting the clove population. Furthermore, highly productive mother trees were selected from this population with the criteria of production average 80 kg tree−1. In addition to their production potential, their morphological characters and chemical compound content were also observed. Twenty mother trees with a production potential of more than 100 kg of flowers tree−1 were selected as high yielding trees. The morphological characters of the selected trees do not resemble any of the released varieties. The content of essential oils and main chemical components is following the Indonesian National Standard of clove quality. Twenty highly productive trees can be recommended for further research for use as sources of quality seeds.

Engineered Biosynthesis of Pharmaceutically Important Compounds.

Natural products are an important source of medicinal seeds. The discovery of novel biosynthetic enzymes from nature is important for their use as biocatalysts for the enzymatic synthesis of useful natural products. In addition, genetics and structural biology developments have enabled the engineering of enzymes for the production of unnatural analogs of bioactive natural products. In this review, I describe the recent research on these two topics, the exploitation of a novel secondary metabolite enzyme involved in the biosynthesis of the sulfonamide natural product antibiotic SB-203208, and the production of unnatural bioactive depsipeptides by reconstruction of the modular enzyme assembly lines in the microbial host.

The role of women in managing sustainable forestry based on local authority and needs analysis of the local agroforestry system in North Sulawesi

Forests have an important role regarding climate change both in mitigation and adaptation efforts. Indonesia is one of the countries with the most extensive tropical forest systems in the world. However, Indonesia experienced the highest level of forest destruction in Southeast Asia. For this reason, Indonesia needs to apply the principles of Sustainable Forest Management to improve the condition of forests through reducing deforestation without compromising the improvement of the welfare of the surrounding community, both men and women. Previous studies prove the involvement of local communities, both men and women, who consider their local knowledge and wisdom is a determining factor for realizing the objectives of Sustainable Forest Management. Previous studies regarding improving the welfare of forest farmers have ignored the needs of both men and women. Similar studies have not been done much in Indonesia or at the global level. There is less research on local knowledge/knowledge that examines how gender differences determine differences in local knowledge/wisdom that men and women have and their respective needs regarding forest resources. For this reason, this study generally aims to increase knowledge about the differences in local wisdom/knowledge possessed and the perceived needs of both men and women who have the potential to rehabilitate forests while improving their lives. This research is the third study in Barangkalang Sangihe Village, located around the protected forest of Mount Sahendaruman. This study uses qualitative data collection methods concerning local wisdom and the needs of men and women relating to forest resources and management. The principle of triangulation is applied to data collection methods and sources. Data collection is done by interview, discussion and observation. Data sources are farmers and village leaders and social organizations. Data analysis uses a qualitative data analysis approach. The results showed that the subconscious of women in particular and the whole community in general who have absorbed the pattern of forest growth that is diverse, structured from high to lowest creeping, is the superiority of the community around the forest. The superiority of this subconscious can be used as a basic capital to develop forest agriculture (agroforestry) that supports each other (mutualistic symbiosis) with protected forests above. Protection Forest can be maintained well only by the community around the forest who can feel the positive impact of the existence of the protected forest, for example as a source of water and as a source of plant seeds (plasma nuftah). Commercial tree crops managed by farmers in the area around the forest cannot be ignored for their biological function for environmental preservation. Because commercial crops, among others, cloves, nutmeg, coconut, and sago, also perennial plants that have deep roots and are also managed like the growth of forestry plants are not regulated like modern plantations.

Evaluation of the growth and yield of true shallot seed on the application of two technology packages during two planting seasons in Central Sulawesi

True shallot seed (TSS) considered to be used due to their technical and economis feasibility. The aim of the study was to evaluate the growth and yield productivity of TSS and shallot bulbs generated from TSS. The study was conducted in Kotarindau Village, Dolo District, Sigi Regency, Central Sulawesi. The seeds was planted on dry lowland area. The experiment was arranged using a Randomized Block Design with two treatments, namely the Introduction Technology Package and Farmer Technology Package during two planting seasons. Each treatment was repeated 13 times. Parameter observed were the growth and yield of shallot. The data obtained were analyzed using the T test. The results showed that the Introduction Technology Package had a significant effect on several components of shallot growth and yield compare with the Farmer’s package in the first (using seeds) and the second season (using bulbs). In the second planting season, the number of bulbs was 7-9 times higher than in the first planting season, and the productivity was 2-3 times higher. We can conclude that the shallot bulbs harvested from the seeds have the opportunity to be used as a source of seeds for the next planting season.

Performance of Eucalyptus tereticornis provenances in subtropical climate

Eucalyptus tereticornis has a wide natural geographic distribution from Papua New Guinea to South Australia (6º-38º S), therefore, it is expected the existence of important differences among provenances. Although differences in performance among provenances have been reported in several countries, the existing information is insufficient to allow the choice of the most appropriate provenance as a source of seeds for commercial plantations for humid subtropical climates. In order to evaluate the performance of 20 provenances of E. tereticornis in Uruguay and to generate information that contributes to the identification of the best provenances for humid subtropical climates, survival, individual tree volume, stem straightness and forking were assessed at 9-years-old in 4 sites in the center, north and northeast of Uruguay. Significant differences among provenances for all traits and significant provenance by site interaction for survival, individual tree volume and forking were found. No provenance was best in all sites. The Buckenbowra provenance had simultaneously high volume and survival. The absence of a clear regionalization, coupled with a significant provenance-by site interaction, suggests that local evaluation of different provenances is essential to identify appropriate seed sources, both for tree breeding and for use in commercial plantations.