Plant protection with inorganic ions.

Gradients of salts of the specific ion repellents for Meloidogyne incognita -- NH, K, Cl, and NO -- have been demonstrated to shield tomato roots from infestation in soil. The strategy of these greenhouse experiments was to interpose a salt barrier in a soil column between the plant roots and the nematodes. The relative effectiveness of the salts as a barrier to infective second-stage juveniles in a sandy loam was NHNO, NHCl > KNO > KCl. Some of these ions are beneficial to plant growth, and the results suggest that a new environmentally tolerable means of plant protection is possible.

Strong repellency of the root knot nematode,Meloidogyne incognita by specific inorganic ions.

Simple inorganic salts of the ions K(+), NH 4 (+) , Cs(+), NO 3 (-) , and Cl(-) are strongly repellent to infective second-stage larvae of the root knot nematode,Meloidogyne incognita. Some of these salts are known to be beneficial to plant growth. The results suggest a new means of plant protection.

Quantitative bioassay for chemotaxis with plant parasitic nematodes : Attractant and repellent fractions forMeloidogyne incognita from cucumber roots.

A simple, flexible, and quantifiable bioassay for the attraction or repulsion of plant parasitic nematodes to or from root fractions or pure substances is described. Accurate gradients of volatile and nonvolatile substances can be measured and established. The method entails placing the nematodes in narrow agarose tracks such that their movement is essentially linear and the distance a population has traveled away or toward a given substance can be monitored with time. Plastic plates, each containing 10 such tracks, are described. The method is illustrated with second-stage larvae ofMeloidogyne incognita and a volatile attractant and nonvolatile repellent fraction obtained from cucumber roots.

Acute neurologic and psychiatric complications associated with cocaine abuse.

This report reviewed 996 emergency room visits and 279 hospital admissions of patients with complications of cocaine abuse seen at the San Francisco General Hospital between 1979 and 1986. In 143 cases, acute neurologic or psychiatric symptoms were the primary complaint, and case-notes provided sufficient detail for analysis. The major neurologic complications included one or more seizures (n = 29), focal neurologic symptoms or signs (12), headache (10), and transient loss of consciousness (six). Psychiatric disturbances included agitation, anxiety, or depression (33), psychosis and paranoia (24), and suicidal ideation (18). The most serious consequences were found in patients with prolonged seizures or strokes, those who jumped out of buildings, and those who attempted suicide by overdosing with other drugs. There was no correlation between the appearance of complications and the reported route of administration, the amount of cocaine used, or prior experience with cocaine. The number of patients who are seeking hospital attention for these or related complaints appears to be rising substantially. Cocaine abuse, regardless of the use pattern, is associated with a variety of potentially severe neurologic and psychiatric complications.

Analysis of vesicle fluid following the sting of the lionfish Pterois volitans.

Fluid aspirated from blisters following a lionfish (Pterois volitans) sting was analyzed utilizing combined capillary column gas chromatography and negative ion chemical ionization mass spectrometry. Analysis for prostaglandin F2 alpha demonstrated 16.91 ng/ml, for prostaglandin E2 0.143 ng/ml, for 6-keto-prostaglandin F1 alpha less than 0.1 ng/ml (nondetectable) and for thromboxane B2 1.65 ng/ml. Platelet aggregation studies showed that blister fluid caused aggregation of isolated platelets only, which was inhibited by heat treatment or by the presence of normal donor plasma.

Retention of Resistance to Meloidogyne incognita in Lycopersicon Genotypes at High Soil Temperature.

Lycopersicon glandulosum and L. peruvianum clones and L. esculentum cultivars 'VFN8' (resistant) and 'Rutgers' (susceptible) were tested for their resistance to Meloidogyne incognita (race l) at soil temperatures of 25 and 32 C. L. esculentum cv. VFN8 and L. peruvianum Acc. No. 128657, both of which possess the Mi gene, were resistant at 25 C but were susceptible at 32 C. L. glandulosum Acc. No. 126443 and L. peruvianum Acc. No. 270435, with combined resistance to M. hapla and M. incognita, and L. peruvianum Acc. Nos. 129152 and LA2157, with resistance to M. incognita, were highly resistant at both temperatures. In a second experiment three of these accessions under heat stress simulated by 32 C ambient and soil temperature retained a high level of resistance. Two clones of L. glandulosum Acc. No. 126440, with resistance to M. hapla, were moderately susceptible to M. incognita at 25 and highly susceptible at 32 C. M. incognita produced significantly (P = 0.01) more eggs on L. esculentum cv. Rutgers at 32 than at 25 C. This study supports the existence of genes other than the Mi gene that confer resistance to M. incognita and are functional at high soil temperatures.

Scorpaenidae envenomation. A five-year poison center experience.

This article describes 51 cases of Scorpaenidae envenomation, 45 of which were lionfish stings to aquarists or fish handlers. The primary manifestation of envenomation in all victims was intense local pain. Various other local and systemic symptoms were also noted. Immersion in hot water produced either complete (80%) or moderate (14%) symptomatic relief in 94% of the victims. This simple and effective treatment was generally unknown to emergency personnel treating these patients.

Extraction of Cysts and Eggs of Heterodera schachtii from Soil with an Assessment of Extraction Efficiency.

Techniques are described for the extraction and enumeration of cysts and contained eggs from soil samples. The average recovery of cysts from seeded soil samples of differing soil texture was 82.7 +/- 2.1%. Recovery from sandy clay soil samples seeded at 1 cyst/100 g soil was 63.4 +/- 5.5%; at 4.2 cysts/100 g soil recovery was 89.6 +/- 1.8%. Recovery of cysts from naturally infested clay soil was 88.3 +/- 2.05%. Egg extraction efficiency for seeded samples was calculated as 78%, and for naturally infested soil was estimated as 83%.

Influence of Nonhosts, Crucifers, and Fungal Parasites on Field Populations of Heterodera schachtii.

Heterodera schaehtii egg number decline under nonhosts was surveyed for 3-4 years at soil depths of 0-30 cm and 30-60 cm in three fields in the Imperial Valley, California. In the two fields continously cropped to alfalfa, annual decline rates were 49 and 63%, respectively, and did not differ (P = 0.05) between depths. In the third field, cropped to annual nonhosts and fallowed, decline rates of 56 and 80% at 0-30-cm and 30-60-cm depths, respectively, were significantly different (P = 0.05). Egg hatch is the major cause of decline. Soil moisture in relation to type of cropping sequence apparently influenced egg hatch and activity of fungal parasites. An interaction matrix is used to assess the importance of biological, environmental, and management factors affecting decline of H. schachtii egg numbers. The required rotation length to non-hosts for various egg densities can be predicted. In coastal California, inclusion of a winter crucifer crop in the rotation increased H. schachtii egg density up to threefold.