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needles og seeds

Using a sequence-based approach, we investigated the transmission of diverse fungal endophytes in seed and needles of Pinus monticola, western white pine. We isolated 2003 fungal endophytes from 750 surface-sterilized needles. In contrast, only 16 endophytic isolates were obtained from 800 surface-sterilized seeds. The ITS region was sequenced from a representative selection of these endophytes. Isolates were then assigned to the most closely related taxa in GenBank. Although 95% of the endophytes in needles from mature trees belonged to the Rhytismataceae, 82 unique ITS sequences were obtained from at least 21 genera and 10 different orders of fungi. Significantly, none of the endophytes in seed were rhytismataceous (chi(2) = 180; P < 0.001). Similarly, needles of greenhouse seedlings yielded only non-rhytismataceous isolates, whereas seedlings of the same age that had naturally regenerated near older white pines in roadless areas were colonized by rhytismataceous endophytes almost to the same extent as in mature trees. Only one of 17 rhytismataceous isolates were able to grow on a medium containing only 0.17% nitrogen, whereas 25 of 31 non-rhytismataceous endophytes grew. Rhytismataceous endophytes are dominant in needles of P. monticola, but they appear to be absent in seed, and unlikely colonists of nitrogen-limiting host tissues such as the apoplast.

Needles og seeds

Needles OG is a weed strain . Needles OG has 21% THC and 1% CBG. The dominant terpene in this strain is myrcene. If you've smoked, dabbed, or otherwise enjoyed this strain, Needles OG, before let us know! Leave a review.

Needles OG is a weed strain . Needles OG has 21% THC and 1% CBG. The dominant terpene in this strain is myrcene. If you've smoked, dabbed, or otherwise enjoyed this strain, Needles OG, before let us know! Leave a review.

Since it was not possible to identify all seedlings emerged from the soil seed bank and some understory species, the correspondence between them was established only partially. Morphotype richness in the understory was higher than that of the seed bank, suggesting the importance of seed bank sampling throughout the year. However, it is also possible that limited time for germination allowed in this study underestimated the real composition of the seed bank. E. coccinea and M. minutiflora turned out to be less important in the understory that in the seed bank. It is possible that shading under the canopy inhibited their growth after emergence. On the other hand, Scleria sp., the most important species in the standing vegetation had a frequence of only 13% in the seed bank. This lack of correspondence has been found numerous times (Korb et al . 2005, Sakai et al . 2005, Hopfensperger 2007, Lang & Halpern 2007, Zobel et al . 2007, Bossuyt & Honnay 2008) and has been attributed to biological differences among species (seed viabilidad and/or likelihood to be predated) or to methodology (germination technique, time of sampling, number or volume of soil samples) which may limit quantification of the soil seed bank (Brown 1992, Malo 2000, Csontos 2007).

Moles, A. & D. Drake. 1999. Potential contributions of the seed rain and the seed bank to regeneration of native forest under plantation pine in New Zealand. New Zeal. J. Bot. 37: 83-93. [ Links ]

Fenner, M. & K. Kitajima. 1999. Seed and seedling ecology. In F. Pugnaire & F. Valladares (eds). Handbook of functional plant ecology. Marcel Dekker, New York, New York, USA. [ Links ]

Since it was impossible to identify all morphotypes, similarity between vegetation composition and seed bank could not be calculated. However, only 20% of the understory families were represented in the seed bank (five families), although they differ in importance (Appendix). E. coccinea , the dominant in the soil seed bank, was the fourth most important in the understory, while M. minutiflora , second in the seed bank, was the 13 th in the understory. Scleria sp., the dominant of the understory, appeared only twice in the seed bank (Appendix).

Hopfensperger, K. 2007. A review of similarity between seed bank and standing vegetation across ecosystems. Oikos 116: 1438-1448. [ Links ]