J. B. Valenciano

Chickpea (Cicer arietinum L.) response to zinc, boron and molybdenum application under field conditions

Abstract In Spain—Europes leading chickpea producing country—chickpea (Cicer arietinum) is mainly cultivated on non-irrigated soils with low native fertility. This study was carried out from 2006 to 2008 in the province of León, Spain, under acid soil field conditions, with the aim of determining whether the application of zinc (Zn), boron (B) and molybdenum (Mo) improved chickpea growth and yield on acid soils. A split-split-plot design with three replications was used. Chickpea responded only to the Zn and Mo applications. At maturity, plants fertilized with Zn and with Mo had a greater total dry matter production and seed yield, mainly due to an increment in pod dry matter. For Zn, the highest yield was obtained with 2 mg Zn per plant (6.80 g plant−1), whereas for Mo the highest yield was obtained with 1 mg Mo per plant (6.73 g plant−1). Interaction was observed between B and Mo, interpreted as indicating that Mo can counteract the effect of B application.

Evaluation of the occurrence of bean plants (Phaseolus vulgaris L.) affected by bean seed fly, Delia platura (Meigen), grown under different sowing techniques and with different forms of pesticide application

Abstract The bean seed fly, Delia platura, attacks the seed or the cotyledons of bean seedlings before sprouting. The larvae penetrate the germinating seeds or the seedlings and mine the cotyledons, the small shoots and/or young roots, before sprouting, causing widespread damage. This work was carried out during 1998 and 1999 in the province of Leon, Spain, using replicated split–split-plots in which the primary, secondary and tertiary factors were, respectively, bean landrace, pesticide application system and sowing technique. Highly significant differences were noticed as regards application of pesticides, which reduced damage significantly compared with controls. As regards sowing techniques, significant or highly significant differences were noticed in the 1999 plots only, where the number of plants damaged was lower on the flat with substrate added to the sowing line. A significant or highly significant interaction between pesticide application and sowing technique was found in all the plots except one.

Evaluation of the occurrence of root rots on bean plants (Phaseolus vulgaris) using different sowing methods and with different techniques of pesticide application

Abstract Root rots are the main diseases caused by soil fungi and their incidence can vary according to seed treatment and sowing techniques used. They cause loss of plants, limit establishment, and canlead to reduced plant development. There are negative correlations between yield and the presence of root rots. This work was carried out in 1998 and 1999 in the province of León, Spain. The factors investigated were respectively —bean landrace (Phaseolus vulgaris), pesticide application system, and sowing technique. Differences were noticed in response to sowing techniques where the number of damaged plants was higher with sowing in furrows (mean, 1.31% plants affected). With regard to pesticide application differences were only observed at Ribas in 1999, where there was reduced plant damage (83% with seed treated and 97% with soil treated in the row). There was a significant pesticide application by sowing technique interaction at Ribas 1999. Rhizoctonia solani was detected in 91.8% of affected plants.

Response of irrigated common bean (Phaseolus vulgaris) yield to foliar zinc application in Spain

Abstract Common bean (Phaseolus vulgaris) is susceptible to Zinc (Zn) deficiency. The objective of this study was to verify the influence of foliar application of Zn on irrigated bean yield in northwest Spain. The work was carried out during 1999 and 2001 in the province of León. The design was a split‐plot design and the primary and secondary factors were, respectively, Zn dose (0, 50, and 100 g Zn/ha) and the number of Zn applications (1 or 2). Yield was increased with Zn foliar application to 20.74 g/plant at 50 g Zn/ha (17.0% increase) and 20.62g/plant at 100g Zn/ha (16.3%). However, there was no significant difference between applied Zn concentration and the number of applications. Pods per plant were increased when foliar Zn was applied (12.3% at 50 g Zn/ha and 14.5% at 100 g Zn/ha, to 12.27 and 12.52 pods/plant, respectively). The increased yield was the result of the increased number of pods/plant.

Use of suction-trap and Moericke traps for monitoring the migration of damson-hop aphid (Phorodon humuli) (Hemiptera, Aphididae)

Abstract Field catches of Phorodon humuli during 2 years (2000 and 2001) by means of Moericke and suction trap were compared in the province of León (north‐west Spain). Positive correlations between the catches with Moericke traps and the catches with the suction trap were found. Positive correlations between the catches with the suction trap and the appearances of the first colonies on crops were also found. These results show that suction trap catches are useful for monitoring the start of spring flight of P. humuli and could serve as a guideline for application of treatments for control of this aphid.