Masters in Forestry | The effect of various physical seed coat scarifications and chemical treatments were studied to determine presowing prescriptions that would ensure uniform, fast and high germination in seeds of Trichi Iia emetica and Vangueria infausta. The studies involved eight 3x5 factorial model experiments arranged in a randomized block design with with 4 blocks each. For each of the two species, two different experiments were conducted in the laboratory and repeated in the nursery. The first experiment of Tri chi Iia erne t i ca involved 3 types of physical seed coat scarification and soaking the seeds in gibberellic acid (CA3) at 5 concentrations; i.e. 0, 250, 500, 750, and 1000 ppm. A second experiment involved 3 types of physical seed coat scarification and soaking the seeds in potassiun nitrate (KNO^) at 5 concentrations; i .e. 0.0, 0.2, 0.4,0.6 and 0.8%. The first study involving Vangueria infausta included 3 types of physical seed coat scarification and treatments of the seed with 5 concentration levels of hydrogen peroxide (H202); i .e. 0, 2, 4, 6 and 8%. In the second experiment, 3 types of physical seed coat scarifi- cation and soaking the seeds in 5 concentration levels of indole acetic acid (IAA); i.e. 0, 25, 50, 75 and 100 ppm were studied. Unscarified seeds of Trichi Iia emetica (without chemical treatment) atta­ ined cumulative germination of 29% and 35%, while seeds with complete removal of both the aril and the seed coat attained cunulative germination of 94s and 93« in the laboratory and nursery experiments respectively.

1 Smoke-stimulated germination in the post-fire flora of California chaparral does not appear to be triggered by nitrate. Application of freshly prepared unbuffered KNO3 solutions (pH c. 6.2) failed to enhance germination of five populations of Emmenanthe penduliflora or one Phacelia grandiflora population, regardless of light or stratification conditions. 2 KNO3 buffered at acidic pH (or unbuffered solutions equilibrated with atmospheric CO2) did induce germination, but KNO3 solutions at pH 7 failed to induce germination. Induction of germination is therefore not due to the nitrate ion per se, but rather to high [H-], although buffered controls gave weak germination at low pH, suggesting a role for H+ plus nitrate. However, other anions such as sulphate were equally as effective as nitrate at breaking dormancy. 3 The germination response to KNO3 was affected by the type of filter paper used and this may be linked to differences in pH. 4 NO2, at concentrations present in biomass smoke, was highly effective at inducing germination, and other oxidizing agents also induced germination. 5 Several growth regulators, including nitrite and gibberellin, were stimulatory only at acidic pH, but KCN was stimulatory across a broad pH range. 6 Germination decreased at smoke exposures longer than a few minutes. Also, smoked water samples effective at breaking dormancy were acidic and were less effective when buffered to pH > 7. 7 Physical scarification of the seed coat induced germination but the effect was not due to penetration of a water barrier, or to enhanced oxygen uptake or to wound responses such as CO2 or ethylene production. 8 Different effects of the gibberellin inhibitor CCC (chlorocholine chloride) suggested that the mechanisms of scarification-induced and smoke-induced germination may differ. 9 We conclude that either oxidizing gases in smoke and/or acids generated on burnt sites play a role in germination of post-fire annuals in chaparral.

Seed health evaluation of farmer seeds in Cavite, Laguna and Quezon, in 1993-1995, and in Iloilo and Nueva Ecija [Philippines] 1995 wet season, revealed that the physical seed quality of farmer seeds had 88-95 percent seed purity, rice mixture of 4-12 percent, weed seed contamination of 22-35 weed seed/40 g, and 80 percent germination. Those physical qualities indicate that farmer seeds are way below the quality standard set for certified seeds. Nueva Ecija farmers' seeds with a purity of 96.7 percent, best seeds of 50 percent, high germination index and low lethal seed infection were better than farmer seeds from Iloilo followed by farmer seeds from Cavite-Laguna-Quezon. Farmer seeds from Cavite-Laguna-Quezon are characterized by low rate of germination index (below 70 percent), more rice mixtures and weed seed contamination, suggesting the poor condition of seeds for planting. Under the Farmers Participatory Research (FPR), the performance of high quality IR64 seeds is signficantly better than farmers IR64 seeds in terms of physical seed quality and seedling vigor and had less seed infection. The yield of high quality IR64 was 8 percent to 14 percent more than the farmers' IR64 seeds. IR64 high quality seeds was 9 percent to 18 percent higher in yield compared to the rice yield of farmers not involved in FPR. These yields increase averaged P2,866.00/ha during the 3 seasons' trial in Nueva Ecija. Farmer seed practices like winnowing, flotation, physical seed sorting, chemical and biological control agent for seed treatment were evaluated in IRRI [International Rice Research Inst., Los Banos, Laguna, Philippines] Farm. Using farmer seeds of varying qualities the seed treatment practices demonstrated varying effectiveness in improving seed quality before planting and yield response. Physical seed sorting on selected farmer seeds gave significant yield increase of 8-20 percent over the untreated original farmer seeds. This indicates that farmers can still do seed management practices that would improve his available seeds before planting and improve the yield. Based on 8 farmer seedlots used in the 4 seasons of yield trial, chemical seed treatment gave an average increase in yield of 6.75 percent which translates to P2,457.35/ha; the use of BCA (1.6 percent) equivalent to P604/ha; flotation with 3.8 percent valued at P1788/ha; winnowing and flotation combination with 4.34 percent valued at P1,359/ha; and physical seed sorting with 14.88 percent and valued at P5195/ha. The farmer seeds needed improvement in seed purity, removal of varietal mixtures, and weed seed contaminants. Winnowing and flotation of rice seeds were effective in removing partly filled grains, other plant parts and majority of weed seeds. Physical seed sorting by trained persons was efficient in improving seed purity, in removing discolored seeds and other impurities

Horticultural Intergenerational Therapy (HILT) is a successful program that uses horticulture to benefit the elderly by increasing their physical activity and mental stimulation. It also benefits youth by introducing them to concepts of horticulture as well as showing them how to cultivate relationships with the elderly. Tells how to plan a HILT program, organize participants, and obtain funding. Includes long-term activities, such as planning an outdoor garden, planting bulbs and seeds, drying flowers, and building birdhouses. Provides lists of materials needed to accomplish each project, 30 ways to hold gardeners' interest, and factors influencing germination.

"Para determinar tiempo, costos y repetibilidad de ensayos de calidad de semillas en distribución de chile, tomate, cebolla y melón, se realizaron pruebas físicas y fisiológicas y se cuantificó el tiempo utilizado en cada prueba, así como los costos totales de cada ensayo y se determinó la repetibilidad de los resultados al repetir tres veces todos los ensayos. Se observó que en las pruebas físicas y fisiológicas los resultados de los ensayos en cebolla no fueron similares a los indicados en etiqueta, principalmente en pureza física y germinación estándar. En la prueba de germinación estándar se observó una tendencia de resultados más altos en la modalidad de siembra entre papel que en la modalidad sobre papel. El cultivo de melón presentó en sus cuatro lotes mejores resultados en todos los ensayos realizados. En relación al tiempo de realización la prueba que requirió de menor tiempo fue Peso de mil semillas y la de mayor tiempo vigor mediante el ensayo de deterioro controlado. En cuanto a costos el costo más bajo fue pureza física y la de mayor costo vigor (DC). Los coeficientes de variación obtenidos fueron de una unidad, manifestando la confiabilidad de resultados. La rentabilidad se determinó basándose en los costos obtenidos agregando un 30 por ciento para establecer el precio del servicio, encontrándose dentro del rango en costos de otros servicios ofrecidos dentro y fuera del país." | "To determine time, cost and repetibility of seed quality test of pepper, tomatoe, onion and muskmelon; physical and physiological test were developed. Time, cost and repetibility of each test were cuantified, each with theree repititions per test. It was observed that the physical and physiological test results were diferent from the ones indicated in the labels, mainly for puye seed and standard germination tests. For the germination test it was observed a tendency for higher germination resultas with the top paper than between paper system muskmelon presented the highest results for all four seed Iots in all the tests developed. In relation to time consuming the test that required the least time was weight of one thousand seeds and the test that consumed more time was vigour test (controlled deterioration). The coeficient of variance for all test were of one unit, demostrating confiability on the results. The rentability was determined based in the cost obtanied and aditional 30 percent factor to estabilish the price of the prices of the seed analysis service was in the range of prices offered at other seed laboratory services in an out the country."

Four cultivars of Sudanese sorghum (Sorghum bicolor) were analysed for their phytate content, with respect to effects of processing operations, namely milling extraction, water soaking, malting, heat-treatment and fermentation. The conditions of processing used were: decortication to give an 80% extraction meal; 12 and 24 h soaking in tap water; 96 h germination; fermentation for 3,6,9 and 12 h; and cooking at 95 degrees C until starch gelatinized. Total phosphorus, phytate phosphorus and phytic acid were determined. Results showed that phytic acid phosphorus formed > 85% of total phosphorus of the sorghum cultivars studied. All treatments investigated caused phytic acid reduction to various extents. Enzymic methods of phytic acid removal (fermentation and malting) were found to be more effective than physical extraction methods, i.e. milling, soaking and heating.

Soil physical structure regulates the storage capacity and flow of different compounds and energy, and affects crops through four fundamental properties: mechanical impedance, and availability of water, oxygen and energy for root growth. These properties are commonly expressed as mechanical resistance to metal probes, water potential, oxygen diffusion rate, and soil temperature, respectively. The combination of climate, soil types and system of production dominant in Uruguay determine high frequency of occurrence of sub optimal levels of these variables for wheat production. The main problems that were identified are: a) low availability of thermal energy for crop emergence, which determines long seed-emergence periodsb) oxygen deficiency for germination and early deep root developmentc) high mechanical impedance in the upper soil layersd) soil water deficiency during tillering and reproductive phase. Wheat crops are able to compensate yield components to a large extent. Therefore, problems occurring early in the season do not have a large impact on productivity. However, in high-yielding environments, negative effects may occur. On the other hand, water deficiency in later crop stages would more likely impair grain yield potential. In the present work, recent experimental developments are presented, and several hypothesis for preventing and alleviating soil physical restrictions are formulated. The need to improve the currently low rain-water use efficiencies (6-10 kg ha-1 mm-1) by agricultural practices that increase soil water infiltration capacity is stressed.

The experiment was conducted in order to measure the extent of physical damage and its effect on the physiological quality of bean seeds harvested during different development stages. Bean seeds of Bayomex, Flor de Mayo de Mata and Pinto Texcoco cultivars were used. Samplings were taken 101 days after planting until completing six harvesting dates. After harvesting the treatment was applied and consisted in the free-fall dropping of seeds on a hard concrete surface from different heights of drop, 2, 4 and 6 m. The physical quality of the seed was measured in terms of moisture content and physical damage (sodium hypochloride immersion), while the physiological quality was assessed in terms of germination and vigour (accelerated ageing). By delaying the harvest the physical damage increases mainly due to the decrease of the seed moisture content. Physical and physiological qualities are significantly affected when the seeds are exposed to free-fall dropping from higher heights. The highest physical and physiological quality was obtained in the seeds not exposed to damage (control treatment). Varietal differences were observed on the susceptibility to physical damage and on the effect of this on the physiological quality. Key words: Bean seed, Phaseolus vulgaris L., harvesting date, physical damage, physiological quality. | Se estudio el dano fisico en semillas de frijol en manejo postcosecha para determinar su magnitud y su efecto sobre la calidad fisiologica de semillas cosechadas en distinto estado de desarrollo. Se usaron variedades Bayomex, Flor de Mayo de Mata y Pinto Texcoco y a los 101 dias de siembra se iniciaron muestreos hata completar 6 oportunidades de cosecha. Despues de la cosecha se dejaron caer las semillas sobre una superficie solida de concreto a caida libre de 2, 4 y 6 m de altura. La calidad fisica se midio con base a contenido de humedad y dano fisico (inmersion en hipoclorito de sodio) y la calidad fisiologica se evaluo en terminos de la germinacion y del vigor (envejecimiento acelerado). La demora en la cosecha aumenta el dano fisico por reduccion de humedad. Se afecta significativamente la calidad fisica y fisiologica cuando las semillas se exponen a caidas de mayor altura. La mas alta calidad fisica y fisiologica se obtuvo en semillas que no se expusieron al dano (testigo). Hubo diferencias varietales en la susceptibilidad al dano fisico y en el efecto de este sobre la calidad fisiologica. Palabras clave: Semilla de frijol, Phaseolus vulgaris L., oportunidad de cosecha, dano fisico, calidad fisiologica.

Hybrids were obtained after in vitro germination of embryos from interploid crosses between triploid ‘French' plantain cultivars (Musa spp. AAB group). ‘Ntanga 2' and ‘Bobby Tannap' with diploid banana (Musa acuminata subsp. burmannicoides) ‘Calcutta 4'. Cross-pollinated bunches were harvested at full maturity and ripened with acetylene in a room for 4 days. Seeds were extracted from peeled ripe fruits by squashing. Embryos from the seeds were excised aseptically after 2 days and germinated in vitro. Seedlings were subsequently planted in early evaluation trials after acclimatizing in the greenhouse. Chromosome counts were carried out on root tips of mature and maiden suckers to determine ploidy levels using a modified squashing technique. Counts showed that two of the hybrids were aneuploids (trisomics) with somatic chromosome number of 2n = 2x + 1 = 23. One hybrid was diploid while the other two were tetraploids. Tetraploids are the most promising hybrids for the genetic improvement of plantains. Diploids are valuable material for further improvement of the plantain genome at this ploidy level. Trisomics provide means for further characterization of the Musa genome and physical gene mapping in plantain and banana.

Scorpiurus subvillosus L. represents an interesting legume species to take into account for pasture improvement in Ragusa plateau. This species exhibits hardness in seedcoat which limits seed germination and plant establishment. Experiments involving mechanical (by hand and within a scarifier), physical (high temperature in hot water and ultra-low temperature in liquid nitrogen) and chemical (sulfuric acid) treatments were carried out, in order to overcome hardseedness and promoting germination. the species differently responded to the seed treatments, with hand scarification and sulfuric acid scarification for 30 min being the most effective in breaking dormancy (99-100% of seed germinated). Nevertheless, the hand scarification is not practical on a large scale and the acid treatment could damage embryo with prolonged exposures. Ultra low temperature in liquid nitrogen joins a good effectiveness with little danger of damaging the seed, to apply to a large quantity of seeds | [Scorpiurus subvillosus L. rappresenta una specie di leguminosa interessante da tenere in considerazione per il miglioramento dei pascoli nella piana di Ragusa. Questa specie presenta una durezza nel tegumento del seme che ne limita la germinazione e l'insediamento delle piante. Sono stati condotti esperimenti su trattamenti meccanici (a mano e con uno scarificatore), fisici (alta temperatura in acqua bollente e temperatura ultra-bassa in azoto liquido) e chimici (acido solforico), allo scopo di superare il problema della durezza dei semi e di migliorare la capacita' germinativa. La specie ha risposto in misura differente ai trattamenti al seme; la scarificazione a mano e il trattamento con acido solforico per 30 min risultavano i piu' efficaci nella rottura della dormienza (99-100% di semi germinati). Ciononostante la scarificazione a mano non e' praticabile su larga scala e il trattamento acido potrebbe, a seguito di esposizioni prolungate, danneggiare l'embrione. La temperatura ultra-bassa in azoto liquido unisce una buona efficacia a limitati rischi di danneggiamento del seme e puo' essere applicata a grandi quantita' di sementi]