Abstract Herbarium-based studies and extensive field work revealed the existence of a new species in the genus Manihot which is restricted to the municipality of Itirapina, in the state of São Paulo, Brazil. Characteristics such as the size and morphology of the leaves and bracts were important to recognize M. irregularis as a new taxon. Description, illustration, as well as comments on its morphology, distribution, conservation status, and a key for the identification of Manihot species for the state of São Paulo are presented.

Abstract The objective of this study was to evaluate the stigma morphoanatomy and receptivity in ten promising papaya accessions, to expand knowledge useful for genetic improvement of the culture. The morphoanatomy was analyzed by light and scanning electron microscopy, and the stigma receptivity was investigated by application of hydrogen peroxide and α-naphthyl-acetate with fast blue B salt, in pre-anthesis, anthesis and post-anthesis. The papaya accessions presented dry stigma surface, presence of one to six erect stigmatic lobes, with structures joined to the upper base of the style and covered with numerous elongated unicellular tubular papillae, distributed on both faces of the epidermis. The morphoanatomy had a similar pattern in all the accessions, differing only in the timing of floral development. The stigma receptivity in some accessions occurred even before floral opening, continuing with greater intensity in anthesis and post-anthesis. Pre-anthesis is the stage least propitious for controlled hybridizations due to the weak or absent stigmatic receptivity. The results obtained provide information on the floral stage that is most propitious for fertilization, as well as supporting future investigations of the botanical morphology of the species.

Abstract: Due to the increasing search for renewable resources, plant fibers have become an alternative when creating new products. Studies demonstrate the potential use of pineapple fibers in composites. The objective of this work was to evaluate the genetic diversity and verify any association between ISSR (Inter Simple Sequence Repeats) bands and quality of pineapple fibers for use in cements in the civil construction. The study analyzed the genetic variability of 11 pineapple genotypes, as well as the possible association of 131 bands from 16 ISSR markers with fiber quality characteristics. Eleven bands were selected based on their high correlations (0.64578* to 0.72457*) with three fiber quality variables. Of these, two bands were purified, sequenced, and blasted against sequences in GenBank at NCBI. These markers can be used in marker assisted selection to genetically improve the quality of pineapple fiber. Bands that returned no hits in the NCBI BLAST search can be deposited as new sequences in the GenBank. Therefore, the SCAR markers, once validated, can be useful in pineapple genetic breeding programs worldwide by using molecular marker assisted selection for fiber resistance, which could subsidize the development of more promising genotypes for industrial use and contribute to the sustainability of this new production sector.

Os parasitóides Lysiphlebus testaceipes (Cresson) e Aphidius colemani Viereck desempenham importante papel na regulação das populações de afídeos que atacam crisântemo em ambientes protegidos. O objetivo deste estudo foi avaliar a interação controle biológico e resistência de plantas, por meio do desenvolvimento e parasitismo de L. testaceipes e A. colemani no pulgão Aphis gossypii Glover mantido nas cultivares comerciais de crisântemo suscetível Yellow Snowdon (YS) e resistente White Reagan (WR). O experimento foi conduzido em câmara climática à temperatura de 22 ± 1°C, UR de 70 ± 10% e fotofase de 12h, utilizando ninfas de 2º e 3º ínstares de A. gossypii atacadas apenas uma vez pelos parasitóides. O desenvolvimento foi de 15,0 e 12,9 dias, para L. testaceipes e de 17,0 e 16,3 dias para A. colemani em A. gossypii nas cvs. YS e WR, respectivamente. O parasitismo por L. testaceipes foi maior em A. gossypii na cv. YS (68,4%), quando comparado com WR (50,0%), sendo que para A. colemani não houve diferença significativa (46,8 e 35,0% para YS e WR, respectivamente). As porcentagens de emergência de L. testaceipes e A. colemani em A. gossypii mantido em YS e WR foram, respectivamente 91,6% e 85,3% e 78,1% e 100,0%. A longevidade de A. colemani e a taxa de parasitismo de L. testaceipes foram influenciadas negativamente pela cultivar WR. Os resultados indicam uma interação positiva entre controle biológico com parasitóides e a cultivar resistente WR no controle de A. gossypii em crisântemo em sistema protegido.

The parasitoids Lysiphlebus testaceipes (Cresson) and Aphidius colemani Viereck play an important role on the regulation of aphid populations on chrysanthemum grown in greenhouses. This study evaluated the interaction of biological control and plant resistance by the development and the parasitism of L. testaceipes and A. colemani on Aphis gossypii Glover. The aphid host was kept on commercial cultivars of chrysanthemum susceptible Yellow Snowdon (YS) and resistant White Reagan (WR). The experiment was carried out in climatic chamber at 22 ± 1ºC, 70 ± 10% RH, and photophase 12h. Nymphs of 2nd and 3rd instars of A. gossypii attacked only once by the parasitoids were used in the experiment. The development time was 15.0 and 12.9 days for L. testaceipes and 17.0 and 16.3 days for A. colemani kept on A gossypii on cvs. YS and WR, respectively. The parasitoid L. testaceipes showed greater parasitism rate (68.4%) on A. gossypii on cv. YS than on WR (50%), and for A. colemani was not found significative difference on parasitism (46.8 and 35% to YS and WR, respectively). The emergence rates of L. testaceipes and A. colemani were 91.6% and 85.3% on A gossypii reared on YS, and 78.1% and 100% on WR, respectively. The longevity of A colemani and the parasitism rate of L. testaceipes were affected in a negative way by the cv. WR. The results indicated a positive interaction of biological control with parasitoids and the resistant cv. WR on A. gossypii control in protected cultivation.