Poor plant stand establishment is a common problem for marigold production. Exposure to seed priming is one of the strategies being used to accelerate the activation of plant growth, especially seed germination in many crops. Therefore, an experiment was conducted to investigate the influence of different seed priming techniques on perform- ance of French marigold. For this purpose, different seed priming techniques: hydro- primng, 50 mM CaCl2, 100 mg L -1 salicylic acid and 100 mg L -1 ascorbic acid were as- sessed. Seeds without any treatment were considered as control. Priming with 50 mM CaCl2 was proved to be the most effective treatment in enhancing germination and seed- ling vigour among all other treatments including control as shown by higher final germi- nation/emergence, germination energy and lower mean germination/emergence time. Fur- thermore, positive correlation between reducing sugars and dry weight and α-amylase ac- tivity and the concentration of reducing sugars indicates that enhancement due to priming could be attributed to higher reducing and total sugars as well as higher α-amylase activity in primed seeds.
Seed hardening techniques were optimized for vigor enhancement in fine and coarse rice types by evaluating the germination and seedling vigor, and analyzing the electrical
conductivity of seed leachates. Seeds were hardened for 12 h (1cycle), 12 h (2cycles), 18 h
(1cycle), 18 h (2cycles), 24 h (1 cycle) or 24 h (2 cycles). All the seed treatments resulted in
vigor enhancement in both fine and coarse rice types except seeds hardened for 24 h (2 cycles) that behaved similar to that of control. Maximum vigor enhancement as indicated by high germination and seedling vigor, and lower electrical conductivity of seed leachates was noted in seeds hardened for 24 h (1 cycle), which was similar to that of seeds hardened for 12 h (2 cycles) in both rice types.
Se investigaron las variaciones espaciales y temporales de aerosoles de material particulado (PM, por sus siglas en inglés) en Faisalabad, Pakistán, de junio de 2012 a abril de 2013 para conocer la distribución de componentes químicos y fracciones granulométricas en todas las estaciones del año.Se controlaron cuatro fracciones de PM (partículas totales en suspensión [TSP, por sus siglas en inglés], PM 10 , PM 4 y PM 2.5 ) en utilizando un dispositivo de alto volumen para toma de muestras de aire.Las muestras de TSP (144) se sometieron a un análisis químico cuantitativo para determinar la presencia de elementos traza (Pb, Cd, Ni, Zn, Cu, Fe) mediante espectroscopia de absorción atómica, así como de cationes solubles en agua (Ca 2+ , Mg 2+ , Na + , K + , NH 4 + ) y aniones (Cl -, SO 4 2-y NO 3 -) por cromatografía iónica.Las mayores concentraciones de PM se observaron en sitios industriales; las concentraciones en cruces de vialidades principales fueron menores, y los valores más bajos se obtuvieron en un sitio remoto.Las concentraciones de PM fueron aproximadamente de dos a 20 veces mayores que los estándares establecidos por la Organización Mundial de la Salud y la Agencia de Protección Ambiental estadounidense.Las partículas gruesas (TSP y PM 10 ) registraron mayores niveles durante el verano y las partículas relativamente pequeñas (PM 4 y PM 2.5 ) durante el invierno, en tanto que las concentraciones de partículas de todos los tamaños fueron menores durante la época de monzones en todos los sitios.Las concentraciones de los diferentes elementos y iones solubles en agua siguieron un patrón estacional similar al de las concentraciones de PM.Los elementos de la corteza terrestre Ca, Fe, Mg y Na fueron los mayor contribuyentes a las TSP, en tanto que las concentraciones de origen antropogénico (Pb, Cd, Ni, Cu y Zn) fueron relativamente bajas y mostraron alta variabilidad espacial.El sulfato (SO 4 2-) contribuyó con 50-60% de la concentración total de aniones y fue la especie predominante de éstos.Se encontró que la precipitación, la velocidad del viento y la humedad relativa fueron los factores meteorológicos que tuvieron mayor efecto sobre las concentraciones de PM.
The present research studies were conducted under laboratory and field conditions. Double cross hybrid maize seeds were subjected to hydropriming, osmotic priming (PEG-10,000), GA3, matriconditioning with compost, press mud or gunny bag for 24 h in the laboratory. Early germination was recorded in seeds matriconditioned with compost and press mud or GA3 in laboratory conditions while all treatments except osmoconditioning exhibited early emergence under field condition. Maximum final germination percentage was recorded for matriconditioning and control treatments under both conditions. Significant differences also exhibited for root/shoot ratio during cold test. In case of field experiment, matriconditioning with press mud, GA3 and hydropriming treatments showed significantly higher grain yield as compared to other treatments.
Seventy diverse genotypes were evaluated for drought stress for morphological (shoot and root length, fresh and dry shoot weight, fresh and dry root weight) and physiological traits (stomatal conductance, photosynthesis and transpiration rate) to increase the area under arid and semi-arid climatic condition to overcome the deficiency of edible oil. All genotypes varied significantly for all evaluated traits. High variability for photosynthesis rate and lower for transpiration rate but highly significant. Genotypic variance and its coefficient are almost higher for all characters then environmental variance and its coefficient. Additive gene action was found for stomatal conductance and fresh root weight, good characters for selection having high heritability with increased genetic advance used to find out drought tolerating genotypes. Genotypes ORI 29 and ORI 30 performed better in normal and drought stress condition can be used further breeding programme as a drought tolerant material. In PCA, genotypes ORI 30, ORI 27, ORI 38 and ORI 105 expressed maximum diversity can be used in further hybrid programme.
Sulphur is the fourth major nutrient in crop production. Most crops require as much sulphur as phosphorus. Canola cultivars has recent introduction in Pakistan's agriculture so information related to sulphur effects on seed yield and seed composition are scanty. A two year study (2003-04 & 2004-05) was conducted to document the effects of sulphur application on seed yield, oil, protein and glucosinolates of canola cultivars. Two canola cultivars and four sulphur levels were arranged in randomized complete design with split plot arrangement. Cultivars exhibited statistically significant variations for protein but non-significant differences for seed yield, oil, protein and glucosinolates. Similarly, sulphur effects on seed yield, oil, protein and glucosinolates were neither significant nor consistent. However, interactive effects were observed to be significant. Seed yield, protein and glucosinolates increased during second year as compared
to those observed during first year, whereas oil content exhibited an opposite trend and decreased during second year as compared to first year. Inverse relationship was observed between oil and protein during both the years of experiments. However, glucosinolates exhibited linear relationship to sulphur levels but did not show any significant relationship with seed yield.
'/%3e%3cpath fill='%23fff' d='m8.751-17.959 10.11 11.373L3.997-9.844l13.94-6.1-7.692 13.129z'/%3e%3c/svg%3e)