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‘Tonda Pacifica’ is a new hazelnut (Corylus avellana L.) cultivar for the kernel market. It was released by the Oregon Agricultural Experiment Station in April 2010. Compared with ‘Barcelona’, Oregon’s leading cultivar, ‘Tonda Pacifica’ has smaller trees, higher nut yield efficiency, smaller nuts and kernels, higher kernel percentage, fewer nut and kernel defects, better suitability for the blanched kernel market, and earlier nut maturity. Kernels have a crisp texture, highly rated flavor and nutty aroma. The kernel quality is similar to that of its Italian parent ‘Tonda Gentile delle Langhe’. The small kernel size is well suited to use in chocolate products and baked goods. ‘Tonda Pacifica’ is susceptible to eastern filbert blight caused by Anisogramma anomala (Peck) E. Muller.

Anthocyanins and phenolics of 10 blue honeysuckle (Lonicera caerulea L.) genotypes were characterized and quantified by HPLC-DAD. Peak assignments were confirmed by low-resolution electrospray mass spectrometry. Six anthocyanins were detected with the major peak identified as cyanidin 3-glucoside. Five additional anthocyanins were characterized as cyanidin 3,5-diglucoside, cyanidin 3-rutinoside, pelargonidin 3-glucoside, peonidin 3-glucoside, and peonidin 3-rutinoside. Four polyphenolics were identified as chlorogenic acid, neochlorogenic acid, quercetin 3-rutinoside, and quercetin 3-glucoside. Two additional unidentified phenolics were characterized as flavonol and hydroxycinnamic derivatives based on UV-vis spectra. Hydroxycinnamate levels ranged from 30.4 to 156.2 mg/100 g, whereas the flavonol content ranged from 12.6 to 32.8 mg/100 g. The L. caerulea subspecies boczkarnikovae contained the highest amounts of hydroxycinnamic derivatives and flavonols.

Blue honeysuckle (Lonicera caerulea L) is a polymorphic species widely ranging over northern regions of both Eurasia and North America. Berries have long been harvested from wild plants in regions of Russia, China, and Japan where superior edible forms are native. During the past several decades, research in Russia and Japan has resulted in cultivars being selected for commercial production. However, this species is virtually unknown in North America as an edible berry. Over the past four years, germplasm has been introduced into Oregon, USA from northeastern China, Siberia, and Hokkaido, Japan. Evaluations were made for plant growth, time of flowering and fruit maturity, fruit traits, and adaptability to a relatively mild, maritime climate. [..]

Dormant scions of ‘Bing’ were exposed to 1–2.5 krad of gamma radiation in order to induce useful mutations. The main buds were excised and the scions grafted to allow the growth of accessory buds into primary (V1) shoots. The frequency and types of mutations on secondary (V2) populations are described. In a population of 3324 V2 shoots, the overall mutation frequency was 6.4%: 4.2% partial, 1.6% total and 0.3% growth-reduced mutants were identified. The experiment was repeated using 3 krad- and 4 krad-fractionated doses in water. Differences in mutation frequency at 3 krad and 4 krad were not significant. Of 2562 surviving V2 shoots derived from the irradiation of accessory buds of both standard and V1 shoots, the overall mutation frequency was 3.3%: 1.7% were partial-leaf mutants, 1.0% were total-leaf mutants, and 0.54% were growth-reduced mutants. For maximum mutation rate with adequate survival we suggest acute irradiation of accessory buds in air at dosages approximating LD50 (2.75–3 krad). A larger mutant sector was present in V1 shoots derived from accessory buds than those from main buds as revealed by the higher number of total mutant repeats in the families.

The U.S. Dept. of Agriculture, Agricultural Research Service, National Clonal Germplasm Repository (NCGR), Corvallis, Ore., maintains Rubus germplasm representing worldwide diversity of the genus. Chromosome numbers were counted for 201 plants representing 124 taxa (species and varieties). There are new reports for 42 taxa, confirmation for 72 previously reported, and 10 counts for plants unidentified to species. The basic chromosome number was seven, and ploidy levels ranged from 2x to 12x.

Chromosome numbers were counted for 90 Rubus cultivars and selections maintained at the U.S. Dept. of Agriculture, Agricultural Research Service, National Clonal Germplasm Repository, Corvallis, Ore. To my knowledge, 37 of the counts are new, including five that are corrections of previously published counts, 30 that are confirmations of numbers that were previously published but assumed from their parentage rather than actually counted, and 23 that are confirmations of previous counts. The basic number was 7, and 2n numbers ranged from 2x to 14x, including odd-ploids and aneuploids.

Hundreds of fruit species with commercial potential are currently in a status of low economic importance. Some, such as quince, pomegranate, and figs, have been cultivated for thousands of years. Others have only been locally collected and consumed from wild populations of the fruit. The development of these underappreciated crops depends on a range of factors including the cultivation limitations, yields, uses of the fruit, and marketing potential. Although initially many crops are developed using selections from the wild, as they are developed, breeding programs work toward improving the crop for both production and quality. This chapter examines nine emerging crops chosen among hundreds of potential crops which are currently showing much promise as commercial crops. These include five tree fruits, namely, pawpaw, quince, mayhaw, pomegranate, and fig, and four berry crops, namely, blue honeysuckle, elder, goji, and ‘ōhelo.

A chlorophyll deficiency expressed as yellowing of leaves was observed in hazelnut (Corylus avellana L.) progenies. Segregation ratios approximated 3 green: 1 yellow, indicating control by a single recessive gene designated chlorophyll deficient #1, for which the symbol c, is proposed. `Barcelona', `Butler', `Compton', `Lansing', Willamette', and the ornamental selection `Redleaf #3' are heterozygous. Pedigree analysis strongly suggests that all heteroxygotes inherited the recessive allele from `Barcelona'. A cross of `Barcelona' with the yellow-leafed ornamental Corylus avellana L. var. aurea Kirchn. produced no yellow-leafed seedlings, indicating that the chlorophyll deficiencies from these two sources are controlled by different loci. Progenies segregating simultaneously for this trait and the gene controlling presence of anthocyanin indicated that the two traits are inherited independently. Seedlings deficient in chlorophyll but with anthocyanin were able to survive under field conditions, while leaves of yellow-leafed seedlings lacking anthocyanin became scorched and the trees died.

The style color of standard hazelnut (Corylus avellana L.) cultivars ranges from pink to dark purple. Styles with an unusual yellow color were first noted in seedlings of the progeny 'Goodpasture' x 'Compton', and the ratio was ≈3 red : 1 yellow. Controlled crosses were made to investigate the genetic control of style color. The same 3:1 ratio was observed in four additional crosses in which both parents had red styles. Two crosses of a red and a yellow parent gave ≈50% yellow styles, while a cross of two selections with yellow styles gave only seedlings with yellow styles. These segregation ratios indicate control by a single locus, with yellow style color recessive to red. Seedlings with yellow styles have green buds and catkins and a more upright growth habit than their siblings with red styles. Inspection of the pedigrees of these progenies shows that 'Daviana', 'Willamette', 'Butler', 'Compton', 'Goodpasture', and 'Lansing #1' are heterozygous. 'Daviana' appears to be the original source of the allele for yellow styles, as it is a known or suspected parent or ancestor of the others. Ratios in a progeny segregating simultaneously for growth habit (normal vs. contorted) and style color indicated independence of the traits. However, in a progeny segregating simultaneously for leaf color (red vs. green) and style color, no redleaf seedlings had yellow styles. The S-alleles of eight genotypes with yellow styles were determined, and indicate a possible linkage between the yellow style locus and the S locus that controls pollen-stigma incompatibility. One expla- nation is that the yellow style trait is conferred by an allele (a ys ) at the anthocyanin (A) locus that controls leaf color. A second explanation is that there is a yellow style locus closely linked to the A locus. The A locus is known to be loosely linked to the S locus. The European hazelnut (Corylus avellana L.) is a monoecious, wind-pollinated shrub that enforces cross-pollination through dichogamy and self-incompatibility. The style color of standard green-leafed hazelnut cultivars ranges from pink to dark purple. Only when branches are bagged to protect female inflorescences from wind-borne pollen do the styles continue to elongate and the color fades from red or pink to light yellow or white. In 1978, in the progeny 'Goodpasture' x 'Compton', styles with an un- usual yellow color (Fig. 1) were noted in ≈25% of the seedlings. The yellow color was present when the styles first emerged and persisted as the flowers aged. We report here the results of an investigation of the genetic control of style color in hazelnut.

Chromosome numbers were determined for the Rubus species and cultivars held at the USDA/ARS National Clonal Germplasm Repository, Corvallis, Ore. Counts were made on a total of 205 taxa; 81 of which were new, 124 were corrections, and a few were corrections of previous reports. The numbers ranged from 2n = 2x = 14 to 2x = 98, and included odd-ploids and aneuploids. Knowledge of the chromosome number of a plant is important for its use in breeding because of potential sterility problems that may arise due to unbalanced gametes. The value of these particular counts are that they are vouchered by a permanent, living plant collection that is available to the scientific user community.

442 Eastern filbert blight, caused by the fungus Anisogramma anomala (Peck) E. Muller, is native to the eastern United States where the wild species Corylus americana Marsh. serves as its host. The disease is believed to have been introduced to the Pacific Northwest on nursery stock imported from the East Coast in the early 1960s. The disease is now firmly established in the northern third of the Willamette Valley, the major growing area, and is a serious threat to commercial acreage of the European hazel, Corylus avellana L. The life cycle of the fungus was described by Gottwald and Cameron (1980). Symptoms include perennial cankers that enlarge 30 to 100 cm·year and can exceed 2 m in length, girdling scaffold limbs and the tree trunk. The canopy of older trees of susceptible cultivars is killed in 7 to 10 years. The most common hazelnut orchards in Oregon are planted to ‘Barcelona’, with ‘Daviana’ pollenizers planted every third tree in every third row. ‘Barcelona’ is considered tolerant of the disease, as infected trees remain productive for several years before eventually dying. ‘Daviana’, however, is highly susceptible. As eastern filbert blight spreads from one orchard to another, it is generally found first in the ‘Daviana’ pollenizers. From there, it spreads to the surrounding ‘Barcelona’ trees. ‘Butler’, the second most common pollenizer, is also highly susceptible. ‘Hall’s Giant’ is considered tolerant and is currently recommended as a pollenizer for ‘Barcelona’, although it sheds pollen later than the ideal time. ‘Gasaway’, which is highly resistant to the disease (Mehlenbacher and Thompson, 1991), sheds its pollen very late in the season and, thus, is a poor choice as a pollenizer for ‘Barcelona’. By replacing the highly susceptible pollenizers in a ‘Barcelona’ orchard with resistant genotypes, it should be possible to delay the time of initial infection and to maintain an infected orchard in a productive state for many years. Four resistant pollenizer selections were

The wealth of small fruit genetic resources present in China is recognized; however, very little collection and subsequent incorporation of this germplasm have taken place. From July to Aug. 1996, we collected small fruit germplasm with Chinese colleagues in northeast China. The collection area was primarily in Heilongjiang and Jilin provinces; from the Russian border (53°N) to the North Korean border and south to 42°N. Collections were made in the Changbai Shan, Xio Hinggan Ling, and Da Hinggan Ling mountain ranges. The primary genera of interest included Rubus, Ribes, Vaccinium, and Fragaria. In addition, species within Corylus, Actinidia, Lonicera, Sambucus, and Schizandra were collected along with ornamental trees, herbaceous perennials, and shrubs when available. Seed was shared with our Chinese colleagues. Collections have been deposited within the USDA-ARS National Plant Germplasm System. The most-promising collections included: an extremely large fruited Rubus crataegifolius population, many populations of Vaccinium uliginosum and V. vitis-idaea from a broad geographic range, large samples of F. orientalis, and a number of populations of the edible Lonicera caerulea. The collected species, collection sites, and observations will be presented.

A pre- or postharvest foliar B application was found to increase fruit set of ‘Italian’ prune (Prunus domestica L.). A prebloom B spray failed to increase set. Neither fall nor spring applications influenced the amount of fruit lost in the midsummer or “blue” drop. All trees involved in the experiment had adequate B by the standard index of tree nutrition, August mid-shoot leaf analysis. Incipient B deficiency did not appear to be involved. Fall foliar B increased B levels in dormant bud and spur tissues and in flower buds and flowers. A prebloom B spray increased B levels of floral tissues to a lesser degree. The highest B concentration was found in the ovary. Boron concentration in flower buds in April following a fall B spray was as much as five times the amount found in mid-shoot leaves in August. August mid-shoot leaf analysis revealed higher levels in leaves from trees treated the previous fall in only one of the 2 years. Several morphological and physiological effects of the fall B spray were observed. Among these were a slight delay in the time of bud break, a decrease in the size of flower buds and mature flowers accompanied by reduction of style and pedicel length, and a decrease in pollen germinability. B level of pistil and pollen had no effect on in vivo pollen tube growth rate.

SUMMARY The interaction of environmental and genetic variation in hazelnut (Corylus avellana) shoot development and the behaviour, survival, and colonisation of eriophyid bud mites (Phytoptus avellanae and Cecidophyopsis vermiformis) were studied. The distribution of galled buds on shoots indicated that mites colonised only those buds formed during the mite migration period. The point of entry is probably the growing shoot tip. Once within this structure, as the shoot develops the mites have access to a succession of newly-formed, bud primordia that are unprotected by bud scales. The relative accessibility of the apical meristem and bud primordia may affect host susceptibility.

Diallele crosses of sibs and parents of 3 parental combinations demonstrated sporophytic type of incompatibility inCorylus avellana L. One gene with multiple alleles was indicated. All 6 alleles present in the 4 parental cultivars and in their progeny exhibited dominance in pollen and independent action in the pistil. Individuals homozygous for S-alleles appeared in progeny of parents having one allele in common. Reciprocal differences occurred in some crosses. The stigmatic surface is the site of the incompatibility reaction. Incompatible pollen germinated abundantly but failed to penetrate into the stigma cells.

Pollen-stigma compatibility relationships are reported for 55 filbert cultivars (cvs) (Corylus avellana L.). A total of 11 S-alleles have been identified amongst 36 cvs for which one or both S-alleles have been established. For the 20 cvs with only one known allele and the 17 for which neither allele have been identified further information is provided as to which alleles can be excluded as possibilities.

A filbert breeding program was initiated at Oregon State University in 1969 to develop improved cultivars for the Pacific Northwest. Nut traits were evaluated in parents and progenies and the first published inheritance data for this crop species are presented. Correlation coefficients of progeny means and mid-parent values are 0.92 for percent kernel, 0.84 for nut weight, 0.68 for amount of fiber on pellicle, 0.89 for kernel shrinkage, 0.70 for number of nuts per cluster, and 0.34 for estimated husk length. It is concluded that all but one of the evaluated traits is highly heritable and that additive gene action is principally responsible.

Pollen-stigma compatibility relationship were studied in 50 cultivars and more than 800 seedlings of the European hazelnut (Corylus avellana L.). A total of 22 unique S-alleles have been identified. Dominance relationships in 75 of the possible 231 pairs of alleles have been determined in both pistil and pollen. In the pistil, all alleles exhibited independent action, whereas in the pollen, alleles exhibited either dominance or codominance. The dominance relationship was linear with 7 levels of dominance.

Nondormant mutants in hazelnut (Corylus avellana L.) are described. In contrast to normal trees in which physiological rest, or dormancy, is induced by short days, mutants fail to respond to this stimulus. Shoot tips continue to grow, old leaves are retained until midwinter when they are frozen and/or pushed off by developing axillary buds, axillary buds begin to grow in December, 2-3 months before normal spring bud break, and cold hardiness does not develop. Nondormancy is controlled by a single recessive gene (dd). The mutation is not uncommon since eight cultivars, including the world's most important commercial cultivars, are heterozygous for this trait. The implications of nondormancy in a temperate tree species are discussed in relation to evolution, extension of the range of cultivation, breeding, and value for basic studies of fundamental mechanisms of dormancy.

Growth and development of the pistillate flower and fruit in Corylus avellana L. cv. Barcelona, was studied from anthesis (January) to maturity (September). Ovary growth is very slow for about 4.5 months, proceeds very rapidly for about 6 weeks, during which time 90% of the increase in diameter occurs, and then abruptly ceases. Ovule development, megasporogenesis, megagametogenesis, and fertilization are described. At the time of pollination (January) the pistillate flower consists of a pair of stigmatic styles joined at their bases by a minute ovarian meristem. Pollen tubes reach the base of the style in 4 to 7 days. The sperm nucleus remains in the pollen tube tip in a resting stage until mid-June (about 5 months). During this period the basal meristematic cells develop into a mature ovary. Multiple megasporocytes, derived directly from archesporial cells, give rise to several megaspores, partly developed embryo sacs, and one normal embryo sac. When the sac is mature a secondary pollen tube, bearing the sperm, grows basipetally from the resting site in the upper tip of the ovary. It proceeds through the funiculus of the anatropous ovule, along the single integument, enters the nucellus through the chalazal end, and penetrates the micropylar end of the embryo sac where the sperm is ejected. While pollination is necessary to initiate ovary development, only a small percentage of the pollinated pistils develop into a full size nut. Fertilization is necessary for the formation of normal nuts with embryos. Full size nuts which are empty at maturity result from pollination without fertilization or from embryo abortion.

Susceptibility ratings for big bud mite Phytocoptella avellanae (Nal.) are given for 144 clones of filberts (Corylus sp.) and for 1850 progeny between crosses involving 21 parents. There is genetic resistance as well as different levels of susceptibility. Susceptibility is highly heritable and appears to be determined by multiple genes with predominantly additive gene action.

A detailed study of mitosis and meiosis in Pyrus species has revealed that all species are diploid, with 2n = 34, though several cultivars and variants are triploid. All diploids had regular 17 II. In triploids, trivalents represented the maximum association, and no cell had more than a total of 17 bivalents and trivalents combined. These data do not support the hypothesis of autosyndesis within the third set of 17 chromosomes. Alternatively, the data support the Sax (1931) concept that the Pomoideae group arose as an allopolyploid between two primary forms having basic numbers of 8 and 9, respectively. Speciation within the genus Pyrus, as in other genera of the Pomoideae, has occurred without a change in chromosome number.

Pollen germination in most Pyrus species was moderately high, usually averaging above 50 per cent. Five species were completely or nearly pollen sterile: P. nivalisJacq., P. ovoideaeRehd., P. Decaisne, P. salicifolia, var. pendula and P. variolosaWall. Microspores appear plump and normal following microsporogenesis. Degeneration of pollen grains occurred in the post-meiotic phase of pollen maturation.

Petreatment of hazelnut (Corylus avellana L.) stigmas with L M or 2 M sugar solutions before pollination with incompatible pollen, or pollination with 1∶1 mixtures of incompatible pollen and finely ground sugars, prevented rejection of incompatible pollen by the stigma surface. Lower sugar concentrations or lower ratios of sugar to pollen were less effective. No specificity for overcoming incompatibility was observed among 18 simple sugars and related sugar compounds.

‘McShay’ is an attractive, excellent quality apple (Malus × domestica Borkh.) with field immunity to apple scab. The fruit is similar in color, flavor, and texture to ‘McIntosh’. ‘McShay’ is named in honor of the late J. Ralph Shay and is a late fall dessert apple well-adapted to Oregon's Willamette Valley. ‘McShay’ is the ninth cultivar to be released by the cooperative apple breeding program of Indiana, Illinois, and New Jersey Agricultural Experiment Stations.

Why aren't there more women horticulturists in the United States? The large number of European women in this field always astonishes Americans traveling abroad. In certain Asian countries, e.g. Taiwan and Thailand, women are represented in horticulture classes in much larger numbers. (This may partly account for the extraordinarily high proportion of Oriental women graduate students in the U.S.) Recently, in our country there has been a noticeable increase in high school girls enrolled in agriculture and participating in FFA. There is also a substantial increase in number of college women majoring in horticulture. A poll of 43 Land Grant Institutions showed that women constitute 22% of undergraduate majors and 14% of our graduate students. A comparison of the present meager representation of women in academic positions (2%), employed by USDA (1.5%), and members of ASHS (1.7%) with the proportion of young women training for careers in horticulture demands a reevaluation of long-held assumptions that horticulture is a masculine occupation. Why such a high rate of attrition between undergraduate training and professional employment?