Effect of storage conditions on post planting water status and performance of Pinus radiata D. Don stock-types

Abstract

-We examined the post-planting effect of storage on the plant quality and initial survival potential of bare-root (BR) and soil-plugged root (PR) of radiata pine seedlings outplanted in wet and dry soils. Seedlings were subjected to planting shock even under well-watered conditions. Although the transpiration rate declined, indicating closure of stomata, water stress occurred as evidenced by the decline in relative water content (RWC) and in the leaf water potential. More than 80% of the PR seedlings and only 20% of BR seedlings transplanted in wellwatered regimen survived. Regardless of storage conditions and duration, seedlings planted under water shortage with a RWC < 50% did not survive. According to these results, it is not advisable to store radiata pine seedlings for more than 1 week when planting is under drought conditions even if the seedlings have soil around roots (PR seedlings).container-grown / drought / field performance / seedling survival / transplanting stress Résumé -Effet des conditions de stockage sur l'état hydrique et l'établissement de plantules de Pinus radiata D. Don avec motte et à racines nues. L'étude a porté sur l'effet du stockage sur la qualité du plant et sur les potentialités de survie initiale de plantules de Pinus radiata D. Don à racine nue (BR) et avec motte (PR), replantées dans des sols humides et secs. Les plantules ont subi un stress de transplantation, même dans des conditions hydriques optimales. Malgré la diminution de la transpiration, signe d'une fermeture stomatique, un stress hydrique est intervenu, comme en témoigne la baisse tant du contenu hydrique relatif (RWC) que du potentiel hydrique. Plus de 80 % des plantules PR et uniquement 20 % des plantules BR ont survécu à leur transplantation dans des conditions hydriques optimales. Indépendamment des conditions de stockage et de la durée de celui-ci, les plantules mises en place sous déficit hydrique, avec un RWC inférieur à 50 %, n'ont pas survécu. Conformément à ces résultats, le stockage de plantules de Pinus radiata pour des périodes supérieures à une semaine est déconseillé lorsque la transplantation se fait sous déficit hydrique, même lorsqu'il s'agit de plantules avec motte (PR).croissance en conteneur / établissement / sécheresse / stress de transplantation / survie

Drought conditioning improves water status, stomatal conductance and survival ofEucalyptus globulussubsp. bicostataseedlings

“…As observed previously a greater allocation to root growth improves seedling survival [8,20]. Midday RWC was also closely correlated with survival, similarly to Mena-Petite et al conclusions [29]. These results confirm that both traits can be considered reliable indicators of initial survival [13].…”

Effect of cold storage treatments and transplanting stress on gas exchange, chlorophyll fluorescence and survival under water limiting conditions of Pinus radiata stock-types

“…In previous papers we have investigated the effects of storage conditions and root coverage on the physiology of seedlings after several days' storage, focusing particularly on how this affects the seedlings' functional integrity and initial survival potential (Mena-Petite et al 2001, 2003, 2004a. Our findings showed that storage caused a decrease in seedling water status and an increase in electrolyte leakage, indicating membrane damage (Mena-Petite et al 2001).…”

“…On the other hand, evidence has been presented showing that field performance potential can be predicted more precisely using limiting environmental conditions (Folk and Grossnickle 1997). This was borne out in a later work where our results (Mena-Petite et al 2004a) showed that the transplants, even when regularly irrigated, suffered from planting shock as exhibited by decreased water potential, which remained low even after the decline of stomatal conductance. Duration of the stress depended on water content at the time of planting and on previous history of stock type (MenaPetite et al 2004a).…”

“…Water shortage causes other physiological and biochemical changes such as turgor loss (Hsiao 1973), disruption of membrane integrity (Tan and Blake 1993;Fan and Blake 1994;Mena-Petite et al 1999, 2000, 2004a, ABA accumulation (Roberts and Dumbroff 1986;Davies and Zhang 1991), photosynthetic inhibition (Grossnickle and Major 1994a, b) and reduction of ammonia assimilation enzyme activity (Mena-Petite et al 2004b). Furthermore, damage to the photosynthetic apparatus may occur during cold storage (MenaPetite et al 2003), which may lead to a lag in the resumption of photosynthesis (Jiang et al 1995).…”

“…Cold storage of forest planting stock has become a widely used and accepted method of storing conifer plants, allowing stock to be lifted under favourable nursery conditions (Sharpe and Mason 1992). However, during cold storage, seedlings are subjected to stress (McKay 1997;Mena-Petite et al 2001, 2003, which in turn may affect their quality and subsequent field performance (McKay and Mason 1991;Mena-Petite et al 2004a).…”