The Influence of Temperature and Moisture Content on the Germination of Peanut Seeds1

Abstract

Peanut seed, (cv. Hanoch and Congo) were stored both shelled and in-shell at various moisture contents and 15, 20 and 26 C, in an apparatus designed to purge air at relative humidities in equilibrium with the moisture contents of the seed. Storage lasted .nearly 6 months and during this period the moisture contents and germination percentages of the seed were examined periodically.The fesults of germination trials showed significant differences between in-shell and shelled seed for the cv. Hanoch, but not for the cv. Congo. The calculated moisture content required to maintain 90% germination for shelled seeds stored for six months at 15 C was 8.0% for Hanoch and 7.9% for Congo. To conserve the same germination level for 6 months at 26 C, the calculated moisture contents were 7.1% for Hanoch and for Congo.Key Words: Groundnuts, seed storage, germination, temperature, moisture content.Peanut seeds may be stored either in-shell or shelled. A general belief is that seed are better preserved when stored in-shell than after shelling. However, the former method has two disadvantages. The first is that in-shell peanuts occupy a far greater storage volume. The second is that a larger percentage of kernels are damaged mechanically during shelling since the in-shell peanuts were stored at a low moisture content (m.c.) to prevent degradation during storage. The higher the level of broken kernels, the lower the germination percentage of the seeds (5).Two factors known to influence the preservation of peanut seed are temperature and relative humidity (r.h.) (6, 9, 10). Molds that affect the germination power of seed are also influenced by the ambient humidity and temperatures in storage (4). However, literature on the comparative preservation of shelled and in-shell peanut seed is limited. According to Gelmond (S), to preserve peanut seed for one year at 21 C, a m.c. of 5% or less is necessary. Boswell et al. (3) reported on peanut seed preservation at different temperatures and relative humidities.The objective of this investigation was to determine the influence of moisture content on the germination capacity of two peanut cultivars, Hanoch (Virginia type) and Congo (valencia type), when stored both shelled and in-shell at different temperatures. Materials and MethodsThe by water addition to obtain the following kernel m.c.'s for both shelled and in-shell seed: for Hanoch 9.5% and 12.5%; and for Congo, 9.0% and 11.0%. These levels were chosen to obtain m.c.'s of each cultivar in equilibrium with air r.h. of 80 and 90%. After moistening, the seeds were placed in and filled, 2-liter containers. On average each container held one of the following: Hanoch 1400 g shelled (1160 seeds), Hanoch 573 g in-shell (310 seeds), Congo 1420 g shelled (2840 seeds), and Congo 520 g in-shell (676 seeds). Through these, air was purged, whose r.h. had been adjusted to 80% and 90% at 15, 20 or 26 C by bubbling through wash bottles maintained at the respective temperature and containing sulfuric acid at suitable concentrations (11). Flow ...

Peanut Seed Vigor Evaluation Using a Thermal Gradient

“…The variation in germination rate among peanut seed lots of cultivars was apparent in 2006, 2007, and 2008 ( Figure 1). Variation in peanut seed quality has been previously noted and can be associated with storage moisture content [34] as well as cultural and harvest practices [35].…”

Impact of Seed Storage Environment on Field Emergence of Peanut (Arachis Hypogaea L.) Cultivars

“…When the storage temperature increased to 20 C and RH was at 79 to 83%, germination steadily decreased to 80% after 80 days and, if stored at 20 C and 85 to 89% RH, germination dropped to 20% in 80 days. Navarro et al (1989) found an interaction between the tested cultivars and the temperature and RH. The cultivar Congo (valencia type) tolerated higher storage temperature and RH better than the cultivar Hanoch (virginia type).…”

“…Maintaining these conditions is not possible when peanuts are stored in warehouses without climate control. Navarro et al (1989) studied the interaction of temperature and moisture concentration on the germination of peanut seeds of different cultivars. Germination of peanut seeds stored inshell (pods stored intact and later shelled to provide seeds for germination) at 15 C and 79 to 83% RH remained above 80% for over 150 days.…”

Nivel de infección fúngica natural en relación a la calidad de semillas de maní

“…Dicha calidad es máxima en madurez fisiológica y a partir de ese momento comienza su deterioro en la planta madre, proceso que continua en la cosecha y poscosecha (Heydecker, 1977;Maguire, 1977;Pérez y Argüello, 1995). Así durante la cosecha y el almacenamiento, la exposición de las semillas a humedad relativa alta provoca deterioro (Ketring, 1971(Ketring, , 1973, el que se acelera por la presencia de patógenos asociados a la semilla (Navarro et al, 1989;Wu y Cheng, 1990;Pereira Goulart, 1993;Mills y Woods, 1994;Faiad et al, 1996;Cavallo et al, 2005). La disminución del poder germinativo puede deberse al aumento en el porcentaje de ciertas anormalidades, sobre todo a nivel radicular, de acuerdo a lo sugerido por Dhingra et al (2001) en soja.…”